Fel-Pro® gaskets offer 100% vehicle sealing with application-specific materials to give you sealing solutions with the performance and durability professionals trust
Fel-Pro® gaskets offer 100% vehicle sealing with application-specific materials to give you sealing solutions with the performance and durability professionals trust
Fel-Pro® gaskets offer 100% vehicle sealing with application-specific materials to give you sealing solutions with the performance and durability professionals trust
Fel-Pro® gaskets offer 100% vehicle sealing with application-specific materials to give you sealing solutions with the performance and durability professionals trust
Fel-Pro® gaskets offer 100% vehicle sealing with application-specific materials to give you sealing solutions with the performance and durability professionals trust
Fel-Pro® gaskets offer 100% vehicle sealing with application-specific materials to give you sealing solutions with the performance and durability professionals trust
This Original Equipment Manufacturer part is the same part that was made & installed by the car manufacturer at the factory where the car was produced.
This Original Equipment Manufacturer part is the same part that was made & installed by the car manufacturer at the factory where the car was produced.
This Original Equipment Manufacturer part is the same part that was made & installed by the car manufacturer at the factory where the car was produced.
This Original Equipment Manufacturer part is the same part that was made & installed by the car manufacturer at the factory where the car was produced.
1992 Pontiac Grand Am-Overheating-Water in engine?
Showing 2 out of
33 Posts
|Show 31 Hidden Posts
Question From huxley on 1992 Pontiac Grand Am-Overheating-Water in engine?
Hey Guys,
Been a while since I've been here-that means I've had some miles without an issue. Not no more...
Stats: 1992 Pontiac Grand Am 2.3L 4 CYL OHC with 39K (yes, only 39K) on the engine. Backstory of this car is that it was hardly ever driven and it sat in storage for quite some time, probably with no proper prep beforehand. Came to me last year. I haven't had it a year quite yet.
New issue: I was driving tonight, saying to myself that I should change my coolant out tomorrow because we're going to have nice weather. I look down on the dashboard, and to my shock, my temp gauge is in the low end of the red zone. No warning lights alerted me at all. I immediately pull into a gas station and take a look under the hood. Engine doesn't feel hot (was driving for about 10 minutes at that point-highway-sustained 65 or so) and I foolishly undid the radiator cap (the overflow is where the radiator cap is located-there aren't two separate ones like some vehicles) protected myself from the assumed spray, and nothing but a light "fss". Coolant was present. No leaks under the car. No leaks in the engine compartment that I could see. Then, I check my oil. Uh oh, somewhat milky on the dipstick. Not cool. So, my first guess was my head gasket. Then, upon looking around and hearing some feedback, I'm told that GM cars, and especially grand ams, usually fail at the intake valve gasket. Whatever the case, how do I know? I drove the car back from the gas station to my house. It stayed out of the red zone, but it was high. I blasted the heat and the heat wasn't any hotter than normal. There was still no issues-the engine did not feel hot to the touch-warm, but not hot. The coolant does not appear to be leaking. Could I be dealing with a different issue here? Could I have condensation in my engine? Could this be something else, or am I on the right track? Damn, how does one know for sure! I experienced the somewhat milky crap on the dipstick before-last winter. It always seems to do it in the cold last year, but after a couple oil changes it stopped. I also threw a small amount of seafoam in the crankcase last year. I'm running 10W-30 Mobil 1 Synthetic in it right now. A little on the heavy side for the colder weather, I know.
My thoughts-could be a head gasket starting to fail, could be the intake valve starting to fail, or it could be that I just have a bad thermostat and it's not letting the engine getting hot enough to burn off any accumulated condensation in the engine because I take short trips in the winter. My tailpipe vapor doesn't seem to be any worse, I don't smell that sweet coolant smell (I'll check again tomorrow) and I didn't noticed any oil blown back into the coolant reservoir. I'm thinking of sending off a sample of the oil to a lab to have analyzed for coolant presence. I can always change the oil too and see if it separates, but I doubt it will. I wonder if changing the thermostat, changing the coolant, and then going on a long drive would help me at all? If I see that gauge start to rise up, I of course would turn my ass around and get back to the driveway in a hurry. Any other thoughts are certainly welcome! And yeah, I know the Quad 4's had head gasket issues. But at under 40k? Jeez, sucky engineers if that's the case.
I feel like I can attempt the intake valve fix, but I don't want to attempt the head gasket. Of course, it's dark out right now, but I can throw up some pictures tomorrow morning and check around the area some more to see if there is a problem I'm not noticing.
Thanks for any and all help-and Tom, if you see this, I hope you're doing well!
-Nate
Response From Tom Greenleaf
NATE! I was worried about you! Obviously you've picked up my distinct art of NOT being concise but no matter - I can read and so can Kitty which is more important! Pics were huge and not conclusive to me anyway.
Allright - let's figure a plan for this. I somehow don't think you have a head gasket issue but never say never with car stuff.
The temp running high and poor heat, milky oil?? suggests a real good flush would really help if only to further diagnose this and YES it may just be condensation - some do that some don't and I don't have a good answer for why but it seems to only happen with cars stored/parked outdoors.
Flush it all out good - take T-stat out and best to just toss it while there anyway. Make sure radiator and heater core get a good clear flush with good flow - both directions.
You need the temp to be right and stay stable. Even if there is a slight gasket leak - intake or head it probably isn't causing what you are observing so much as gunky coolant and poor flow right now.
If pressure in cooling system builds up too fast (feel at rad hose from cold start) that's an indicator of combustion gasses getting into cooling system and it could seep either way putting coolant into system but not tons right now by your observations.
When stable and warm - slowly take off pressure at the cap again (you know to watch out for that!!!!) and see if it re-pressures up soon - it shouldn't when already warmed up so fast.
Ok: We (we are both North easterners) only have so much time before we shut down the garden hoses for Winter so get going with this. Take that recovery tank out completely - rinse and let dry as best you can. I like to use Westley's Bleche-Wite tire cleaner on those as both degreaser and general cleaner - works when it's dry - then wait and water works with it if you are familiar with the stuff and will rinse clean.
Now here's where I'll deviate from usual suggestions of NEVER use magic goo in cars to solve anything. I really like NAPA's "Radiator Sealer and Block Repair" - it's made by Mac's - part # 1712. Put just a couple ounces of that in the clean system (REPEAT - COUPLE-- LIKE TWO OUNCES!) but put it in a hose not in the recovery tank on this job or it will just clot there. This is not a sawdust but more of a gel with some suspended junk in it but just the little bit will work on very small flaws and if it doesn't it needs to be fixed.
Next: Forget DexCool - another GM flick up and not needed. Just use whatever EG is on sale that meets specs for new cars. Now - remember that with the flushing there will be some water left in the block of the engine that won't drain out without two more pages of explaining so find the exact # of quarts this cooling system holds and put no more than one half of that in first when filling - then use just water. Aim for a mix that gets you -25F or so. NEVER EXCEED 50% as damn anti-freeze no matter what claims they make to sell it is a LOUSY coolant! It is needed as an anti corrosive for sure. Don't worry about if one night happens and it's colder than -25F as it won't crack your engine - it just makes slush and contracts NOT expand like plain water. Check your freeze protection checker too. Most anti-freeze testers are wrong so the quart count is the real key.
Change out oil again and do it with engine warm as more gets out. Use whatever oil still rated for new car specs for this round as if there's trouble you'll be back again sooner. My new fav for permanant year round is Mobil 1's 0-30 >>>> has a remarkable character of the best of synthetics such as the site's sponsored oil Amsoil. Boasts right on container that it exceeds all specs for 5-3- or 10-30 oils! *Ask Mikie - he likes it! (you are too young to know that commercial no doubt)
Take your time making double sure all air is out of the cooling system. Can take a few cycles of warm ups and cool downs and you may need to bleed off air at a plug near thermostat or fill it thru a high hose and re-attach. Check, check , check and when heater blows warm and hoses feel right it's close to done getting the air out and will finish itself from there with use.
I/we want to see this keep a stable temp gauge reading and use will tell from this point. I also suggest a new pressure cap - IMO it's ok for cold weather cars to lower the standard a bit but it probably calls for 16lb cap. Just make sure it's the right type for the car.
While you are doing all this, take a good look at the hoses - all of them. Feel for soft spots or if there's been rubbing on one somewhere. Use all care when removing hoses especially ones to radiator and to heater core if you go there. Those necks can break easily and that can be avoided. Sacrifice hoses if needed by slicing them and peeling them off necks.
Good to hear from you even if it is with car questions/problems. Sounds like you are doing well with this car so far,
Tom
Response From huxley
Tom!
Thank you so much for the in depth and quick reply. I think I managed to keep up with almost everything you said (much better than my first days posting here anyway) and my only question is this-WHERE oh WHERE is the thermostat on this beast? I'm told it's the cylinder head by my book, but I just don't see it. Do I need to remove that metal cover on top of the engine to get to it? I think I do, and I think it's on the right most side of the engine where I see the upper hose ending. Am I thinking right?
Something else I noticed, and tell me if this is weird-I turned the car on tonight, again, and let it idle for a minute. I felt the hoses during this time and they felt soft and not very warm. I know there's a rule here about an upper hose being cool then the thermostat is stuck closed and lower hose it's stuck open, or vice versa. They both felt mildly cool and they both felt like there wasn't fluid in them. I'm wondering if I'm simply somehow OUT of coolant. Anyway, I will take your advice and I will replace the coolant, the thermostat, and the radiator cap. The current one is rated at 18PSI. Should I keep that the same or put it on down to 16?
Thanks again Tom and I'll try to keep in better touch here, Nate
PS-Did I ever tell you that I picked up a RWD 95 Chevy Astro? Power steering pump needs replacement I think (shudder) but hey, it runs. Now I just need to screw with it!
Ok: That thermostat is a pain in the butt - figures huh? Get out the 1/4 drive sockets and you'll get it. Link shows pics which may help.
Engine drains/plugs: They are there and could be hidden behind starter motor or who knows. You don't need to drain them at all IMO but would if you were doing some other work or if this was in a marine application when you need the engine completely dry. It will just have plain water there trapped after flush but know it's in the quart count for mixing. It should still flush out fine without touching those.
************
Astro PS pump. If you are sure it's bad - usually keeps buzzing when known full of fluid then seriously consider a good used one, complete with CORRECT pulley and reservoir ready to bolt on. Rebuilds may not come with everything and screw you up with tools needed. Make sure pulley isn't bent in a replacement and has the exact # of grooves in pulley. It's been my experience that pumps last near forever unless run dry from a leak so good is good in my book.
Puter's off for a while. Check out the link on t-stat and go for the lower pressure cap as IMO it's just less strain on the old parts of the system,
T
Response From huxley
Hey Tom,
Alright man, having some hiccups here...
Best way to drain the system? Having issues getting that bottom hose out, just doesn't seem to want to go. I'll probably get it when I head back again, but damn, it's a pain.
The THERMOSTAT?! Where IS this thing? I looked at the pics, I still don't get it. There are two different places I'm looking at that seems like it would be the thermostat. Why can't this damn thing just be a drop in...
The first one is immediately to the right of the top part of the engine, behind the power steering fluid reservoir, underneath the belt and back a little bit. It's set at an angle though, a severe angle. The second one is behind the exhaust manifold, somewhat set back and somewhat underneath it. I'm actually thinking that's it, because there is a connecter going into it and it looks like it's by itself and it's straight up and down. Also, the gasket I have looks like it would fit in there. Regardless of which one it is, both seem to be a huge pain in the ass to remove and I'm a bit lost.
Help Tom!
-Nate
Response From Tom Greenleaf
Ok: get the gasket for the t-stat and that will show what item it's at. I recall one of these that was under a radiator looking plain cap at the radiator - is there something like that?
To get hoses off to drain is a pill too. I'll try to find a picture of a cotter pin puller which is great for chasing around the sticky hose to outlets/inlets without damaging them. There may or may not be a drain in this radiator at all - I plead "no contest" - can't remember. Ok: - There's the cotter pin puller set you can chase under hoses with. Just a hook that's not too sharp would do. If hose is going anyway just cut it with box cutter and peel it off. Use a smear of rubber friendly grease to help put new ones on and for easy removal later if needed.
T-stats are usually at the highest hose on way to radiator at the engine. There are exceptions but few - just luck this is one maybe
Hey - whey you get to t-stat it may be in the side and stuck there. Replacement needs to be stuck in place so it doesn't fall when tightening up. Small amounts of gasket cement and let dry, wire that you can pull thru later and stick it to housing. Know that some are "eliptical" and may be marked "top" and also be sure it's in the right direction for flow - most won't go backwards. Just don't let it slip down out of your sight and tighten at all costs. Take other crap out of the way to get as best a shot at it as possible.
Keep at it. It's really best to go new if you are flushing this out anyway. If monster bucks for it you can test it out in a pan of water to see action and temp it opens at,
T
Response From huxley
Hey Tom,
Ok, still having trouble. I got the hoses off that I needed to get off, but the thermostat is not where I thought it was.
I undid the thing I was talking about behind the exhaust coming off the back of the engine. NOT the thermostat there. Whoops. It actually seems to be some sort of transmission part, as it got trans fluid all over my hands when I took it out to study it. Had some weird plasticy gear thing on the end. No clue. Had a wire hooking into it, seemed like the gasket would fit there. I was wrong.
Now, the other thing I mentioned earlier, it could be that too...but I'm not sure. I'm loathe to try and take this off now too in order to figure it out. It's in SUCH a pain in the ass position and it's almost sideways-could that really be it??
I'm posting a picture of what I think it may be now-let me know what you think...but I could be very wrong again. I wish I had a damn diagram of this engine. The haynes manual sucks.
and another view
Any idea Tom or anyone else? Sigh...
Thanks, Nate
Response From Tom Greenleaf
Nate - What happened???? That's your pic of the upper hose to the t-stat housing and the gasket looks like that below or shows to side of your pic. See the large hose and the clamp? That's it! Two bolts or studs with nuts is all I could find and the housing looked the same for a possible variations of the 2.3..
I don't recognize what's in the first pic you showed??
Again: Almost all thermostats are in a housing at the engine end of the upper radiator hose or at least the larger hose going to to highest part of the engine. Hope you get whatever that was with trans fluid back in ok??!!
T
Response From huxley
Play by play update...
Just changed all the spark plugs while I was thinking harder about the thermostat. They're all anti-seized up and properly torqued into the engine head.
I DID get that component back in ok and I screwed everything back together. I called up a local dealership and they led me to believe the thing I was messing with was the correct part. Big mistake ever listening to them. So, that's all set. Don't know what it was, don't care-I put it back on and I think it's fine. Trans fluid change is coming soon, so a new filter will be with it and that should take care of any possible issues there.
Ok so that pic is of the thermostat housing. Good lord, could they make that any more difficult to replace? What are they thinking? It's almost necessary to take off the PS fluid reservoir to even get in there to work. Drat. I did take the airbox off for the time being and I'm going to go back in there and see what the deal is. I'll let you know how I make out in an hour or so.
Thanks for all the help Tom, much appreciated man!
-Nate
Response From huxley
Alright, found the damn thermostat-that was indeed it. So, now I'm wondering the best method to get this old gasket off of there. I hardly have any room to work. The unit will only come back a very limited amount. There is a steel hose hooked up to the other part that does not allow it to move very far. I tried gently scraping, but that isn't doing much. Should I try a razor? A chemical of some sort? I don't want to get this infernal thing all back together to have it start leaking on me...
-Nate
Response From Tom Greenleaf☆☆☆☆☆Top Rated Answer
Whew - you had me scared again but things sound good now. Couple notes on the above posts.....
* Changing trans fluid and filt is good for it.
* Anti- SEIZE on plugs so they don't weld into head is fine but use sparingly and just on the threads - don't get hands dirty with the silver stuff as it conducts electricity and can cause a problem. I like to use silicone grease - some always nearby in a cup with a flux brush for threaded anythings that would stick or rust.
*GASKET REMOVAL - Yes the sprays may help - watch out where overspray goes. You are dealing with alloys and they are easy to gouge up so go easy - razor blades are fine but watch what you are really cleaning off. I have an assortment of gasket scrapers sold as such or make your own as I have. Take some old flat head screwdrivers and bench grind them to a scraper - plain propane torch will bend even light tool steel and you can create quite the dental assortment of scrapers and diggers for grooves surfaces and things. They sell kits too but I've always made some up as said. SERIOUSLY - use care with alloy metals - you can really damage stuff fast. The housing for typical thermostats can be taken to a wire wheel bench grinder type thing to get real nice as well as threaded bolts used to clean up threads. Threaded bolts that go into water jackets if any in this case should have some sealer on the threads. It's old as the hills but I still like the molassass like gasket cement with brush in cap stuff for threads to engine cooling system parts or into water jacketed items. I like to stick new thermostat either in the housing cover or in the block with the most minimal "permatex" gasket maker which is just enough stickyness and a touch of help to seal - plus when and if back there you don't have to fight scraping gaskets off again.
Use care with gaskets and sealers not to use too much - for the most part they help stick things and you don't need extra goo going into areas it doesn't belong.
One more on thermostats, gaskets etc. The housings can break if overtightened. You'll notice they sell those aftermarket as it's too common for that to happen. The items that might be threaded into cooling system parts including t-stat housing are plumbing thread and again I like that brown molassas type thread sealer for those. Even though the thermostats and areas are a PITA get used to it as that's where sensing items are placed for gauges, fan switches and things that need to know the engine's temp of course.
Smile Nate - as cars go you'll look back at this one as being easy to get to things compared to some. Even my personal favs for cars have their tough spots,
Tom
Response From huxley
You're a great man Tom!
I figured it all out, I got it all back together, and I drove the sucker on the highway for about 10 minutes. Didn't overheat. I let it idle and the fan switched on like it was supposed to. The car seems to run "hotter" than it used to, at least according to the gauge inside the car. However, that thermostat could have been either overcooling for some time OR it could have not been accurate I guess. The only weird thing I noticed is that the temp gauge inside the car seemed to be fluctuating while I was on the highway. Is this normal for a freshly flushed radiator? I'll keep my eye on it, but the gauge NEVER got anywhere near the red mark, so that's where I'm happy. I also installed those new plugs and I can really feel the difference in the acceleration of the car. It's somewhat impressive actually.
So, Tom, thank you so much for all the help-for once I actually saw a project through start to finish the day after I had the problem! As always I appreciate the help, I don't know where I would be right now without you, you gave me my freedom of movement back!
Take care and happy halloween, Nate
Response From Tom Greenleaf
Nate - Flattery will get you everywhere - thanks for the kind words.
Ok: The temp reading you see now may be the correct reading but should be steady without much fluctuating especially this time of year without high temp extremes in the scene.
As always, keep a sharp eye on it. It may need something still but nice for now that it's staying within norms. What many vehicles experience is air that takes a while to finish purging out. It can take days of assorted driving conditions to totally stabilize in some. If this doesn't calm down to stay at one spot or dang close pretty soon let's check that out further then.
Run heat full temp request and open window if too hot for you. It's part of mixing up all the coolant and moving along any left over air till it finds its way out. Doesn't take much to show up as fluctuations at first but should quit it. Might even be late with the electric fan or something like that.
The fan isn't really used much when moving along but what does count is air flow, unobstructed thru grille. Some license tags even are placed in lousy spots AND all the shrouding must be in place - even that plastic air dam underneath that frequently breaks off on those parking bumper things and folks don't always put them back - they really do channel air for proper flow especially for above 40ish mph driving. Double check that fins on A/C condenser if air conditioned is clean and in between that and the radiator is clear. Leaves and crud can build up in between and make a problem. You may need to remove a plastic shield up top to even see what's hiding in that area.
It would be a bummer but a faulty new thermostat could also be possible. Let's wait and see how things work out before we blame that.
Also - check anti-freeze concentration. If it reads strong it really can work against you. Take note that system holds pressure of the cap. I use just 7lb pressure caps on all my old vehicles only one newer than this car and have no problems but can in hot weather and will switch back to the OE 15-16lb ones if needed in Summer heat. That trick isn't for everyone.
Sub note and fun fact thrown in here: Pressure of cap does two things. Each "one" pound of pressure raises the boiling point about 3 degrees F which helps keep coolant liquid in extremes as boiling is bubbles and they don't help much for anything in cooling systems - not this time of year of course - I hope. It also tends to hold the hoses open wider for better flow for the extremes too.
*******
Nate - it's always a pleasure and fun to work with you on these projects. My guess is that you and I hold the record for the most VERBOS and longest threads at this site digging into the smallest details.
Keep on truckin' buddy,
Tom
Response From huxley
Hey Tom,
Just wanted to bring you up to speed on the last couple of days of driving.
The fluctuation has chilled out, but I'm not quite out of the woods yet. This didn't happen when I started the car immediately after getting that thermostat in there, but now when I start it, no matter how cold the car is, it immediately reads up 1/4 way up on the internal temp gauge and then will eventually level off about 1/2 way up. Before the problem occurred, the temp gauge would always read as cold all the way to the left and then level off about 1/4 of the way up. It just seems that the gauge is 'off' now. What could be causing this? Otherwise, the car runs fine. It is not overheating at all, there are no coolant leaks or any other leaks that are viewable, etc. The car is in really really good shape all around.
So, in short-that picture is when I first start the car. Usually, that's where the gauge is when the car is already warmed up and it never really went any higher than that. Now, it goes an ever so slight distance over the 220. I know damn well it's lying, but why is it lying?
Hope you're well Tom-and I certainly agree that we hold the record here. Oh-and are you up for a new project soon-that being the Astro? I tracked down my brake line leak and now I just need to figure out if I need to replace the PS pump, lines, seals, or all three. Probably all three. I'll start a new thread for that soon.
Thanks man, Nate
Sorry, you gotta copy and paste the link, I don't want to screw up again like I did with those huge huge huge pictures up above!
(on edit - I tried putting that pic in directly - see how it shows?? - TomG)
Response From Tom Greenleaf
Hey guy!
Do make sure trans fluid is full after that episide.
Believe it or not that isn't the hardest thermostat out there. What it is is YOU needing ten zillion bucks in funky tools that get at hard to get at stuff.
Check out Harbor Frieght, Perhaps Northern Tool (?) for some cheap tools - some you can bend up as needed and I get away with murder with a fav called "wobble head" extentions which allow a 15 degrees round a curve each and a couple 1" ones get in some tough spots. Expensive but old remote carb adjusting ange drivers is handy and throw in the offset ratching box wrenches, even timing wrenches are handy for the nuts and bolts in whacked places.
As time goes on with tools you find you need 10 different styles of just one size of some - then throw in the flare nut heads so you can deal with tubing nuts, crow foot tools - it never ends.
I kinda like 1/4 drive stuff to get to hard to get stuff but of course it isn't strong. Those can finish taking out nuts/bolts and get back in then finish with a stronger tool - less able for the final tighten.
Back when doors and dashboards were my thing and they are a nightmare to get at stuff.
Tools are an investment if you keep at doing you own stuff. First job you may lose to the cost of tools then they are yours. DIY anything is two things - 1. You can save some money... 2. Best of all it's satisfying to do it yourself and know you did it just right and can take more time as needed.
Keep up the great work,
Tom
Response From carconnect
I wish I had advice to offer regarding your engine overheating. But in general, I agree that DIY is just so much more rewarding than relying upon a mechanic. It's exciting to figure out the problem and put together a plan to fix it. Maybe it's a control thing, but I like knowing that I have the ability to manage my car's performance and functioning (to an extent, of course). We should all be master's of our cars, right?
Buying expensive parts and tools is definitely hard to swallow, but tools than can be re-used are a great investment.
Response From huxley
Hey Tom!
It's good! It's fixed! It's back!
I replaced the temperature sending unit-not the sensor next to it-and the gauge is now reading correctly. I'm thrilled! Thank you so much for all of your help on this one. And wow, what a lengthy thread. I'll try to keep the damn things shorter next time. I guess it's that aspiring writer in me...
Take care and thanks again Tom. Next project is the suspension and I'll let you know how that goes!
Much love, Nate
Response From Tom Greenleaf
Here's the ticker tape parade for the success after the longest thread known to mankind for a thermostat and and temp sender but the proof is in the success that it's worth the effort.
Great work Nate. Congrats. It's fun working with you and keeps me double checking my own memory for stuff.
Now for the struts:
You decide how much of that you want to take on or farm out part or all. Please start a new thread for that if you haven't already.
Take care buddy,
Tom
Response From huxley
Hey Tom,
A friend told me about an actual grand am auto owners club that I could hit up for info with this problem I'm experiencing still. I did that and they seem to be fairly lost too. I gave them the background on this problem, gave you and carjunky an honorable mention, and then went from there. If you have time, would you mind taking a look at it and seeing if anything jumps out at you? The thread can be found at http://www.gaownersclub.com/forum/showthread.php?p=1288259#post1288259 and there are some new pictures there.
And this is already written there, but I'm having more problems now. When the car is completely stone cold, the gauge immediately jumps halfway up to the 220 range and then fluctuates between there and the red zone. I also noticed that the upper radiator hose that leads into the therm housing is starting to develop a slight bulge and feels mildly weaker in that area. Any idea on this?
Thanks and I hope you're well! Nate
Response From huxley
Oh and to answer your question regarding when the gauge gave me a reading I didn't trust-it was BEFORE I ever replaced the thermostat. It was at the beginning of this entire issue. I didn't trust that it was actually overheating, but I wasn't sure.
-Nate
Response From Tom Greenleaf
Did you locate the sender for the gauge on dash? It should make the dash gauge not work or change at all if unplugged. It's a thermistor grounding or giving exacting ohms thru it to the needle of the gauge. If wires are pinched they could screw it up - look for that too. So far I'm more apt to blame the sender. There are likely two - one called sender and one called sensor and perhaps another to tell fan to come on for radiator. You will have to hunt for which is for which.
I think temp gauge sensor/sender is on the cylinder head but not certain,
T
Response From huxley
Hey Tom,
So that new issue-did you catch that above post?
Response From Tom Greenleaf
Nate - Ya - about the Astro. Start a new thread for that one. The "joking around" with way2old and others is just us being silly - keeps us going.
Quick note on PS: There's a high pressure and a return line. Pressure side needs to be perfect and that's where you may need to get flare nut wrenches. Plain two sided open end wrenches just don't cut it with flare nuts.......
T
Response From Guest
Hey again Tom
Oh I know, I meant about the gauge being incorrect like it is when the car is turned on. Everything works fine, even the fan comes on, but now the gauge reads higher than it actually is and I KNOW it's lying. Just trying to figure out what the issue might be.
OH! And something else, how do I know I've filled the coolant/water high enough? And where is the best place to fill it from? Should I pull a hose and fill it from a top one somwhere? The top hose going to the thermostat feels almost empty when the car is running.
Thanks,
Nate
These damn vehicles will be the death of me, I swear
Response From Tom Greenleaf
Ok: Let's get this temp thing in order. Please refresh as to where the fill cap is on this car - on the radiator itself or just a pressure cap on the recovery tank? It matters and procedures for filling and problems with air are more of an issue when the only place to fill is the remote recovery tank.
Even now the system should start off with no pressure felt by squeezing the upper radiator hose when cold. When the car warms up - may take a while the expansion will be held at the limit of the pressure cap whether it's on radiator or recovery tank and you can feel that in the upper hose (I say that only because you can feel pressure in the larger hose and they really are all the same pressure - that one is warm to hot - careful of course - but easiest to feel pressure) and in squeezing it you get some idea if it is all liquid or mixed or all air - when squeezed you might see air bubble come out at the recovery tank if you cleaned it.... Air should go out but only liquid return such that enough cycles of cold to warm over and over remove the remaining air by itself - SOMETIMES. If this one is fussy you may need to pull some stunts like jack up the car such that the rad cap or cap to recovery tank is the highest spot OR remove a high hose and fill into the hose - then let the cycles take care of the last bit.
As to just where the temp needle sits - who knows right now what the actual temp really is? It would drive me nuts for it not to read some kind of normal reading and stay steady when warmed up. If not staying steady there's more work to do or a problem still to solve.
How to tell what the temp really is: Infrared no-touch thermometers can peg the real output temp right at the thermostat housing which is where the gauge gets its info. Those are now cheap - check out Harbor Freight for one under $20 bucks if you want one or just use a wired in/out household thermometer or whatever you trust - some meat type automotive ones are fine too, can be put in the output air with heater on low fan and highest temp request on dash will read about 20 degrees lower than the thermostat's # if all is well. This only counts on cars with non automatic temp controls which this shouldnt have. Typical thermostats are about 195F settings. VERY few are higher than that. The thing is marked with the rating now installed of course but the box should say too.
I don't know how quality control does it with these things but most are pretty close to the rating they state. If you really are running at 220F you would be too hot and without a pressured up system it would be boiling and no happy about that.
Note: The boiling point of plain water at sea level is 212F and mixed with anti-freeze is just a few degrees higher. Each pound (psi) of pressure will keep water from boiling another 3 degrees F. That is: - with a 15lb pressure system that works plain water wouldn't boil till 212+45 = 257 degrees Fahrenheit. You've heard of and hope never hurt by opening a hot system which is over the boiling point but liquid and when pressure is released it suddenly wants to be a vapor or boil instantly and that's a hazzard with all liquid cooled engines.
We - YOU need this temp right. The engine was designed to run it's best at a steady temp usually about 195F inside it.
You said it's running higher but within norm on the gauge now but it's hard to really know - huh? It needs to be tested and known. The sender - now cleaned out with flushing and a new thermostat could have an attitude or the dash unit but both usually work or not at all and rarely but I've seen some just read a steady wrong #. Hey - the factory gauge doesn't fragment down to the exact temp well as you can see. I'd still like to be able to trust it though.
Just a thought: The wiring connnection of the sender----- you may have needed to remove or unplug that when working on it. Make sure that's got a good connection and spray the contact areas of plug and spades or prongs with some WD-40 which shouldn't hurt anything. There are a couple senders (I think) in this car - one for gauge and another that tells the fan to come on. If you unplug one and the gauge doesn't read at all or totally wrong that's the one in question.
I don't really know how to test one by ohms in a pan of water but there would be an exact ohm # for the temp it should read.
Ok - so what have I missed or forgotton so far with this?
Tom
Response From huxley
Hey Tom,
Ok couple things-I did unplug the sender, I *think*, while working on it. I had to unplug something to get to it and it was right near the therm housing. I didn't spray it with any contact cleaner, but all the connections on this car are crisp looking. I'll do it anyway just for good measure.
I truly know that the gauge is lying. That picture up above? That is the exact moment the car is turned on-seriously. It sat overnight, I went out in the morning, started it and snapped the pic. It does NOT fluctuate now like it did before-instead it just goes from the initial spot it now rests at to a little over 220-it's like the gauge no longer understands what being at 0 means (or ambient temp). It's really odd...it just doesn't go DOWN to a certain point. Same relative movement like before I ever replaced any of this, just now at a higher reading that will not go lower than that pictured point.
The car has a surge tank only. There is no radiator cap. Really dumb design in my opinion.
The thermostat was 190 I believe. Maybe 195. One of the two definitely.
The system isn't boiling and doesn't feel any hotter than it did beforehand-but I will get one of those infrared guns just to make sure.
Response From Tom Greenleaf
NON-CONTACT POCKET THERMOMETER
Quickly locate hot spots in duct work, electrical panels and automotive systems
Small enough to fit in your pocket
Readings in Fahrenheit (-27° to 230°) or Celsius (-33° to 110°)
ITEM 93983-4VGA $12.99 http://www.harborfreight.com/cpi/gifs/email.gifEmail link to a friend
***********************
That's the pup listed at Harbor Freight - the one for $19.99 had more range but either is a wicked deal. I have one from Radio Shack and they don't carry the little guys anymore.
Ok - with this gauge AFUed right now let's try to figure out if it's the sender or the gauge. GMs are funky as gauges don't always read zero when car is off - or do they - ?? It's late/early - brain is gone and I can't recall. At any rate if unplugged I expect it to read one extreme or another. I know I've messed with them before with a new one in boiling water and quick hook it up to a car to see if gauge reads or not and falls as the thing cools off. I know you have to ground the thing to car with a jumper and be quick plugging it in - all while too hot to touch with bare hands.
If the dang thing is cheap enough I'd just put one in. It will mean lowering the coolant level as it's in coolant with plumbing threads that might be real sticky.
If it's not a problem with the sender I really don't know just how to be sure what to do with the dash gauge end or if wiring to it could be the issue?? I know dash stuff is a total PITA to get at and not mess other things up.
This did work before didn't it? Perhaps you should go back to anything that was touched and see if something is wrong, rubbing, pinched or some screwy thing to cause this now??
I'll be offline for a while now but back within the day.
Later,
Tom
Response From huxley
Hey Tom,
Just wanted to throw an update your way. Haven't had a chance to pick up the thermometer yet. The gauge is still reading the same way-starts at the place in the picture from above when the car is first started on a cool morning and goes a little past halfway up and stays there for the most part. Car doesn't feel any hotter, I can hear the fan coming on when it's supposed to (I assume), and it runs and drives without issue. Still don't quite understand what the problem is here, but I'm sure I'll figure it out soon. Today I filled up the radiator with some more water from one of the top radiator lines instead of the surge tank. It took a bit more water, but not a lot. No leaks to speak of. No more issues with me thinking there is coolant getting into the engine. I'll grab that thermometer soon and get some actual readings to go by.
Oh-and I unplugged the sending unit (or what I thought was the sending unit) and it didn't make a difference on the dash at ALL. Am I maybe not thinking of the right unit? I'll take a pic if needed.
Thanks, Nate
Response From Tom Greenleaf
On your 1992 Pontiac Grand Am 2.3L MFI SOHC Quad , the Coolant Temperature Sensor is located: Under hood, driver side, upper engine area, above transmission housing, mounted in cylinder head
**************
Dunno which you checked for sender for gauge. This suggest the guage sender is in the cylinder head. I dunno right now - if there's no change it may have a pinched wire screwing up the reading for the dash??
It sure would be nice if you could trust the thing with a temp issue and the coolant thing going on. Hope it's not the dash end - don't really know what you would need to do for a 1992 for that?
Refresh my memory - when did this gauge first give you a reading you didn't trust?
T
Response From way2old
OOOOHHHHHHHH!!! !!!!!!!! SINCE YOU GOT THE RAISE, YOU CAN BUY THE DRINKS.
Response From Tom Greenleaf
Nate! We gotta buy the whole crew a round of the good stuff! Check out this ad of our famous "way2olds"'s faviorite anti-freeze on the streets of Boston no less!
Way2old - I can't believe you read this thread this far! I think the site is going to have to upgrade the bandwidth for the forum with this one.
Drinks on the house from Beantown and the Marker's Mark bus!
Tom
Response From huxley
Ok last post for at least 6 hours, I swear!
I was just reading my Haynes manual...it mentioned something about engine drain plugs existing as well to drain all the coolant from the engine. No bs? Where are these? And I'm still a little confused as to exactly where the thermostat is. Everything else makes sense more or less...it'll make more sense once I get in there and start wrenching, no doubt.
-Nate
Response From huxley
Ok I took some pictures because I'm anxious like that...
And I had a few more thoughts-the milky whiteness in the dipstick may not be as big of a deal as I'm thinking. I haven't driven the car in a few days, seriously, and the temperatures have been fluctuating in Syracuse, NY. We've been having below freezing nights and highs in the 50's and 60's throughout the day. Plus, it rained the other day too.
The lack of pressure when I stupidly removed the reservoir cap-normal? I was expecting a lot of "ffhsshsshshsfhfhsfhssshshshshshshhshs" and spray, but I just got a quick "fss" and it wasn't prolonged or very loud. If I was driving on the highway for about 10 miles, shouldn't it have built up some more pressure by then? This points to the problems I feared from earlier, but the rest of it doesn't make sense.
*EDITED OUT PICTURES AS THEY WERE HORRIBLE AND TOO LARGE!
