Shop Gmc Camshaft Position Sensors

Are you sure about that P1351. It doesn't make a whole bunch of sense.


The other 2 codes aren't right either. They have t have been PO171 and PO174

I guess you must be right (I am not at the vehicle now or I would double check) Must have been PO171, PO174 -a lean code for Ox sensors either the upstream or downstream ones, Bank 1 and Bank 2 or something like that. I already replaced one set, before or after.. and as I mentioned this appears to be of secondary concern at the moment, since I have to start the van in order to go to work. P1351 That must be it. I wondered about the crankshaft position sensor. I feel like I am wandering around in the dark. This is no VW beetle (my only repertroir of mechanical know-how).

That wouldn't mean bad 0/2 sensors. That's a lean condition. Check for vacuum leaks or intake snorkel leaks.

Thanks for being there once more, most honorable Hammer Time -and so quick to reply! I believe you that I need to replace the other two O/2 sensors. This little problem persisted even after you got me on the road again last time. But I have been driving it ever since. This new condition (won't start -seems like no spark) is what has got me parked. What can P1351 refer to (High voltage Coil #1 & #4). This is the only new code to appear so without making the mistake of throwing money at the entire list of faults, I hoped to narrow down my focus to this most urgent one. -Or are you saying that the O/2 problem might have caused the starting problem?

I believe you that I need to replace the other two O/2 sensors.

Where did I say that?

I said exactly the opposite that the sensors are fine. You have a lean condition that the sensors are reporting.

There is no PO351. You need to get the code right before you do anything. We could be chasing the totally wrong codes.

Oops, I reread the post and you're correct. You said the O/2 sensors would not be the issue, and yes, as a matter of fact I know I have a little vacuum leak because the hose that attaches to that plastic vacuum "storage" canister came off at the intake area and I cannot see where it belongs. With that said, it sure seems like this is a separate issue from the starting problem - especially since it has been in this condition since we (you) last got this GMC 3500 Econoline van back running with plenty of power. I apologize for being so sketchy with the trouble codes. I will recheck them first chance I get. I think I must have read P1351 -I definitely remember the description: High voltage Coil #1 & #4.

I have now rechecked the trouble codes and this is finally, for sure, the correct readings:
PO171 and PO174 (a lean reading from the O/2 sensors) and I did find a couple of vacuum leaks so I'm hoping this could resolve that particular problem. However, I am still unable to start the engine so I cannot determine that. But the scanner is clearly showing P1351 (no codes present with key on engine off but P1351 appears every time I engage the starter. I have repeated the test many times over and it always states: P1351 Ignition coil #1 and #4 control circuit high voltage Any clues anyone? I am sorry about the confusion regarding the errors in my trouble code reporting.

What's the fuel pressure?

That code still can't be right. you truck doesn't even have "coil 1 and 4 control circuits. It has one coil and one circuit.

P1351 is IC (ignition control) circuit high voltage.

That P1351 code maybe why the engine doesn't start. That code usually pops up when the PCM sees above 4.9 volts on the IC circuit going to the ignition module. The PCM uses the IC circuit to trigger the transistor in the ignition control module to fire the ignition coil.

This is what the diagnostic chart states:

Inspect the wiring and connector at the IC module. Make sure that the IC module is plugged in.

* Take a volt meter and set on it AC volts. Remove the connector from the ignition module and probe the white wire terminal in the connector. Connect your meter's black lead to battery negative. Have someone crank the engine. You should see 1-4 volts.

If you see 1-4 volts, set your meter on DC volts and check for battery voltage on the pink wire in the connector with the ignition on.

If you see battery voltage on the pink wire, set your meter for ohms and check the black wire for continuity to ground. It should be close to zero ohms.

If everything checks out good, replace the ignition control module.


* I question this step because the signal from the PCM is a digital on and off signal in DC volts. Could be in error, but that is what is written in the step.

Gurus,
I did the recommended tests according to the diagnostic chart.
step#1
measured the white wire on end of connector (the order of connector wires: white, black, white, pink)
result was virtually no voltage except an instantaneous surge -(less than a split second) when I began cranking the starter -during the cranking no voltage on both AC and DC scales
measured the white wire in middle of connector (#3 next to pink one)
result was between 1-4 volts on both the AC and DC scales

step#2
measured the pink wire and (at end of connector)
result was almost 12 volts on DC scale
step#3
measured continuity between black wire and ground on ohm scale and got 0.00 on each om level except 200M

We replaced the ignition module (taking special care to apply the thermal paste) and coil (since it was a free exchange) and when that didn't start the engine we replaced the crankshaft position sensor . Still nothing. Now what? Please don't tell me it could be the PCM. The business about the AC scale did seem strange, plus I'm still not certain WHICH white wire is the correct one to test. I also checked for spark at the spark plug wire and definitely no spark.

After clearing the code, does it reappear each time after you crank the engine for thirty seconds? Unplug the injector connector, clear the code, crank the engine for 30 seconds, and see if the code comes back.

Inspect your connector really good. Look for broken wiring inside the insulation near the connector by slighly tugging on the wires to see if the insulation stretches and inspect the terminals in the connector. Make sure the terminals have good tension.

Have you checked for spark using a spark tester?

The ignition control module connector should have letters on it. A-D

A(pink): 12 volt source from ignition. Hot when ignition is run or start.

B(white): IC trigger. Should have between 1-4 V while cranking the engine.

C(black/white): is the ground for the module.

D(white/black): Ignition coil trigger. Should see 12 volts with ignition turned on.

D.S.,
I did clear the code several times (within the scanner tool) and the P1351 did reappear each time. I never unplugged the injector connector -(location?)

I did inspect the connector to the ignition module very carefully, the wires seem tight with no breaks, but I'll double check again.

My method for checking the spark was the old fashioned way -stick a screwdriver in the spark plug wire and hold the metal of the screwdriver 1/4 inch away from ground and watch for a spark to jump to the ground.

I didn't see the A-D letters on the connector (I will look thoroughly tomorrow). But I clearly could see the order and color of wires. On this connector: Pink, then white, then black, and white on the other end. Also this second description of wire color/order is different from your first diagnostic chart. One more little clue I just thought of: This whole no spark/ no start condition just began 2 days ago after it rained all night -the first time it has really rained hard in months.

Sorry, I didn't quite have them in order in the previous post.

This should clarify things:

As best as I can figure:

My pink wire is hot (12 volts) with key on and during cranking
My middle white wire is getting the 1-4 volts during cranking
My black wire is a good ground (no resistance)
My end white wire has virtually no volts (.02) with key on or during cranking -that would be D the terminal for the tachometer signal according to the diagram. You mentioned it should be putting out 12 volts to the coil (correct?) but for this test I would have check the wire while it was plugged into the ICM (correct?) Otherwise, if I am supposed to check the end white wire (D) on the connector that goes to the ICM without it being plugged into the ICM, then I've got nothing with key on or during cranking. Btw, is the vehicle control module (VCM) the same as the powertrain control module (PCM) ie., the computer?

With the ICM connector unplugged and the ignition switch in the run position you should see 12 volts on the white/black wire (D). The module doesn't supply battery voltage to coil. The module grounds that circuit to charge the coil or saturate it. When the module gets the signal from the VCM to fire the coil, it unlatches the ground.

The power for the ignition coil comes from the ignition switch. If you have no power on the terminal (D) and your coil is good, you have a wiring problem because you know you have power on the pink wire from the terminal.

Pull the ignition coil connector and check for 12 volts with the ignition in the run position on the pink wire (A). Then ohm check the white/black wire between the ignition coil and ignition module(C to D). Inspect your wiring and connectors very carefully.

The PCM and VCM both control the operation of the transmission and engine. The only difference is that a VCM also controls an ABS system. What is funny is that GM must of been confused and stuck with the VCM name for the controller even though it doesn't control the ABS system on your van. The ABS system is controlled by the EBCM.

Discretesignals,
Thanks for the precise instructions and helpful corrections. I will have to pick this up again tomorrow when I can return to the van. I do recall the D wire did not have 12 volts (none) with the key in run position. So it looks like I must examine the wiring as you say. Because of your attention I now have some good directions to hunt down the culprit! I shall report back on my investigation. If only I could get some new eyes.

OK,
Here's the latest update on my no start/no spark condition. After double-checking with the volt/ohm meter I got exactly the specified readings on the ICM connector and the coil connector. ie., 12 volts on the pinks, between 1 and 4 volts on the middle white (B) during cranking, no resistance on the black (C) and 12 volts at (D) with the key on, and no resistance between (C) and (D). It still won't start -no spark, and the same P1351 code is present after cranking the starter 30 seconds. Remember I just finished changing the ICM and coil (twice) and the crankshaft position sensor. Where do I go from here?

We are now off the trouble chart. You have an odd one here.

Just for the heck of it inspect the ground eyelet for the module. It is bolted on the inside of the fender near the master cylinder. There is another ground you should check that attaches to the right inner fender next to the battery. This ground goes directly to the negative battery cable. Make sure they are clean and tight.

Do you have a 12 volt test lamp? If you do, unplug the coil connector. Then connect your test lamp to the positive side of the battery and probe the white/black wire (pin C) in the coil's connector. Have someone crank the engine. Does the lamp flash rapidly?

Thank-you for following my peculiar problem with the no spark/no start syndrome. I shall do the recommended procedures when I return to the vehicle. It was pouring rain when you posted last so I will carry on tomorrow. I can use all the help I can get. You're an unique resource and perhaps have no idea the value of the education you provide, along with that other master I encountered, Mr. Hammer Time.
With respect for your work and a grateful user of CarJunky. com advise,
Bob

been watching this thread from afar and i have a question about it. is it possible that the timing is misadjusted causing the high voltage in circuit code beacuse its at the wrong time? if thats ruled out is it possible that there is something wrong with the reluctor ring for CKP sensor?

It's unlikely that the if the distributor was out of synchronization a P1351 would show up. If the distributor was way off, the engine wouldn't start and if it it is was running and off enough it would set a P1345 code for a correlation fault between the cam sensor and the crank sensor. Turning the distributor doesn't affect base timing, it affects cam sensor angle which affects fuel injection synchronization. Remember this system uses the crank sensor on the timing cover to determine the order of the cylinders and base timing.

The way it works is that the PCM is sending a 5 volt digital square wave signal to the ICM to trigger the transistor that turns the ignition coil's primary circuit on and off. The actual signal is between 1 to 4 volts because of resistance in the circuit. It is built that way, so the PCM can recognize an open, shorted to power, or shorted to ground circuit.

The illustration below is an ignition trigger signal in blue that should be traveling on that IC circuit wire. Even though this waveform is for Toyota, the signal is probably similar to the GM's.


If the PCM sees 5 volts all the time on that circuit while your cranking the engine, the PCM assumes the circuit has an open. That is when the P1351 code appears. The open could be in the PCM, wiring, or the ICM. I'm assuming that since that code is appearing, the PCM isn't able to trigger the ICM and that is why he doesn't have any secondary action going on.

I'm attempting to get the OP to check all the wiring and make sure that the grounds are good for those components. It's possible a high resistance ground for the ICM could cause that code. Just using the process of elimination.

The next thing I am going to ask the OP to do is to disconnect the ICM connector and short the white wire IC trigger circuit to ground and then crank the engine. This should cause the PCM to set a P1361 code, which is IC trigger circuit low voltage. If that code sets, that means the wiring from the IC to the PCM is good and the PCM can recognize a low voltage and high voltage condition in that circuit.

If the PCM can recognize an IC low circuit voltage condition, then the only thing I have left to advise is one of two things:

(1) The signal is going to have to be scoped to see what the signal actually looks like.
(2) Use a signal generator to pump a waveform down the IC circuit to simulate the signal from the PCM and see if the coil fires. This would eliminate everything after the PCM.

If the signal looks funky on a scope or a signal generator can fire the coil, more than likely the PCM is the culprit.

Alas, my adventure with this no spark issue is not over. I did indeed have a very sloppy connector at the coil which I by-passed with alternative wiring (strong 12 volts every time now at terminal (D) on the ICM). I repeated every test on the ICM connector (A,B,C,D) and everything checked out: A (pink wire has 12 volts), B (between 2.9 - 3.4 volts when cranking ) C (good ground .3 ohms on 200 scale), D 12 volts with key in run position. I double checked the two grounds DS suggested. A friend said I should check the ECM fuse. There were two (ECM1-20 AMPS and ECMB-20 AMPS) and both were OK (a little bit coroded so I cleaned them up).
I still get the P1351 code after cranking starter for 30 seconds. I read the previous post that advised OP (orignal poster?) to ground the B wire (the wire that is never supposed to put out 5 volts to the IC trigger in the VCM) ie., "High Voltage" to see if it triggers a P1361 code "Low Voltage" and sure enough, it did exactly that. To be precise the code described "control circuit coil #1 and # 4 Low Voltage".
(P1351 ="control circuit coil #1 and #4 High Voltage) This brings up a point that Hammer Time first mentioned, namely that there is only one coil on this engine and, I presume one control circuit.
I did note that Discretesignals recommended one of two final checks (both of which seem beyond me), before concluding the VCM or PCM or ECM ie., the "computer", is kaput. I've been pricing them (between $110 and $200 plus a "computer set-up" fee. The biggest problem is I've been told they have to ship them off (to Florida or somewhere) in order to do this -if it is possible (according the vehicle ID, the part # and whatever else?) Is this the only way to change out the VCM ? I appreciate all the help I have been getting at CarJunky.com

By grounding the IC circuit and getting the P1361, you pretty much confirmed that the circuit between the ICM connector and the PCM is good. It would be really nice to see that waveform on the circuit when you crank the engine to even see if the PCM is generating a signal for confirmation, but I think you pretty much have gone as far as you can with what you have. If it was generating the correct pattern signal, I would say you probably are looking at a defective ICM. It is going to be unlikely that you would have three ICM in row that are faulty, but there is always a possibility.

The VCM does need to be programmed for your vehicle's options. The VIN allows the programmer to select the correct calibration to program the VCM with. You have to understand that the same VCM can be used in other vehicles with different options. The VCMs are physically the same, but its the software that makes them different.

Rats. Could you please confirm where exactly the VCM is located. This is a Savannah 3500 van (box truck). For some reason I thought the computer was accessed inside the cab on the driver's side, inside the fender well just below the spot the brake pedal goes into the master cylinder. Now I'm wondering whether it is inside that black hard plastic case directly below the master and power steering fluid reservoir (that has been leaking onto that plastic case for years- it's very soaked with that fluid) that you get to from the front hood, right next to the fuse box/power distribution station. I can't believe they would put the VCM in such a vulnerable place that looks like it's really difficult to extract. Plus it has 4 distinct harness plugs going into it. The computer harness plug-in connectors I've seen before are always in a long row held by a couple screws -and located in a protected area (inside the vehicle). Is it possible I am looking at the wrong place?

It is in on the left side of the engine compartment on the fender right underneath the fuse relay center and PS reservoir. It does have four connectors with a lot of wires. PS fluid leaking all over it isn't a good thing.

Can you post a pic of the abnormal waveform?

Back probe the coil connector on the white IC control wire and connect a voltmeter and measure the voltage at that wire with the ignition turned on.

If you show no voltage, take a 12 volt test light and connect it to battery positive. With the ignition turned on take the probe and tap on the back probe. Don't hold the probe on there, tap on it like your doing morse code. See if the coil fires.

D.S.,
No, I cannot, at the moment, send the waveform we saw on my friend's Snap-on diagnostic scanner tool (Vantage MT2400-"Power Graphing Meter"). I am too ignorant -(barely learned how to use the computer and navigate cyberspace). But, I can describe it. The tool demonstrated what the pulse should look like: it looked like 3 tall, skinny, identical, rectangular skyscrapers. The waveform we observed when measuring the signal at the CKP looked like one big fat rectangle -went immediately up the graph, then all along across the top until nearly the end of the screen, -and then down again to the bottom.
I did back probe the coil connector wire (the same wire that delivered 12 volts to wire (D- white/black) with the key in run position). That wire showed .02 volts with key off, and no volts with key on. Then we did the morse code test on the white IC control wire (the same one that puts out 1-4 volts with the starter cranking) and sure enough we get a strong spark from the coil wire (secondary circuit) that goes to the distributor. The weird thing is when we back probed the voltage on the IC trigger wire on the ICM we got the following: 1.16 volts with the key off, 3.6 volts with key on. I have the scanner tool with me but I'm not sure where to go next.

The trigger bypass with the test lamp proved that your ignition module and coil are good.

Channel 1 on the scope has to be back probed into the white IC wire at the ignition module. Connect your ground wire to a back probe on the black/white wire at the ICM. Make sure the back probes don't touch each other. The signal is a 0-5 V signal, so you want to set your scope's voltage range close, but not under 5 volts. It's going to be a fast signal, so you probably want your time base around 5ms/division. Your going to have to play with the time base, so you can see the full wave form. Turn your trigger on repeat and set it for the rising edge of the slope at around 1 volt. You don't need an attenuator connected.

Crank the engine and watch the signal. It should be a continuous square wave signal between .4 to 4.5 volts as long as your cranking the engine.

It's funny, but I just had a 96 Chevy 1500 with a 5.7L in the shop today. I should of scoped the trigger signal and posted it, so you could see what a good one looks like.

If you have a camera, can you film the scope? You can upload a video file into a video hosting site like YouTube and then send us the link, so we can analyze your signal.

I just remembered the boss has a 97 Chevy truck 350 Vortec. I'll scope that tomorrow and post the waveform.

This is a guess, but I'm thinking that you have a short to power on that white IC wire somewhere. The reason i'm thinking this is because you stated you had 3 volts sitting on the IC circuit with the key on and you had zero volts on the control side of the coil.

What that is telling me is that some other circuit that has power is shorting to the IC circuit wire and triggering the ignition module transistor to turn on all the time. With the transistor on all the time when the ignition is on or while cranking, the coil is going to be on all the time too. The coil doesn't produce a spark until the transistor is turned off. The waveform would verify this theory. This theory would also explain why the PCM keeps setting the P1351 high volt circuit code. Inspect that white wire really well all the way back to the PCM. Focus on the area you had power steering fluid leaking on to the PCM.

Thanks D.S.,
- for sticking with this, for directing me toward a solution here, and for surmising a little about the real culprit in this mystery. I am going back to the project as soon as it stops raining. I do have a camera, but as I said I'm a definite novice when it comes to uploading, downloading, e.g., - You-Tube, etc. The only thing I'm adept at is sending a picture to an e-mail address. I'll have to study that Vantage scanner tool extensively to even perform the test you suggested, so the first thing on my agenda is to follow the line of logic in your educated guess. This is essentially my mechanic buddy's theory as well. This is why he was suggesting unplugging each connector (all the circuits), one at a time, to see if I can locate a spark from the coil -even if the engine can't start. Then perhaps I can trace how power is shorting to the IC (white) wire on the ICM. Bob

If you have a Vantage, that's not a scanner. It's a portable labscope/DVOM meter. It won't read codes or data.

This is what the ignition control module trigger signal should look like on the IC circuit. I applogize for the noise on the signal. I was in a hurry cause the boss needed his truck.

With the ignition on engine off, there should be no voltage whatsoever on that circuit.


Signal at 10ms time base

What's the latest and greatest? Curious how this one is turning out.

D.S.,
I'm going after the no spark problem again today. I've already been tracing many of the wires that go to the VCM, checking for continuity, shorts, etc. I will give a more extensive report later in the day. I'll definitely be communicating about this nagging (and expensive!) dilemma until I get to the bottom of the mystery. And, thank-you Discretesignals, for staying with me on this tricky one. You and the rest of the bunch at CarJunky.com are a great asset to the school of automotive diagnosis. Bravo!

Have you tried this: Make sure everything is hooked up as it should be on the engine. Take a deep breath. Close your eyes. Say a little prayer. Then see whether the engine will start.

You won't believe this. After weeks of hair-pulling, convoluted, spending-money-out-of-control frustration with my "no spark" problem - after investing countless hours (my time as well as everybody else's) - after getting past numerous hurdles e.g., bad connectors, inaccurate trouble codes, and replacing the ignition control module (ICM) and coil 3 times, the pick-up in the distributor, the crankshaft position sensor (CKP) twice, and finally the computer (VCM) (along with the reprogramming), after all this desperate inquiry into the "no spark" condition...
...I was left in such a quandary that I followed the advice of the last one to post here, some "miracleworker". I did exactly as this one suggested, and do you know what? It started right up. It is running great -like never before! It doesn't make sense, but it's like it is a miracle. This is unbelievable!

Just a bad case of "overanalyzing"

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Alright, Okay, a little sense of humor, -don't cut me off, it's just a little practical joke!
(thanks to my niece for playing "miracleworker")
No, it wasn't really as simple as that. I wish reality could be so easy. Actually, there was some substantial progress, though, in today's endeavors, i.e., we got spark!, we found the culprit and and the engine starts. However, a new problem has developed- (i.e.; the engine shuts down 15 seconds after it starts up and runs) Because of the unusual way I stumbled into the "clue" that cornered the precise cause for my lack of spark I would like to report, in full detail, the extent of my discovery in a subsequent post where I can list the test results, divulge further critical information, and expose my method so I can ask again your advise on what I did wrong and what perhaps I can do about it. Since that explanation is rather lengthy, I just wanted to send this as a heads up before I expound on what happened in greater detail. Still, after all...it did feel a little miraculous.

LOL...your too much.

I caught on just at the last minute you probably kicked your post out. I am sure you got HT though.

Okay, here is part I of a 4 part report. It was supposed to follow DS post #51.
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Part I (of 4)


Masters,
I confess, I was hoping I could pull somebody's leg. I didn't want to go too far out on a limb for fear HT would pound me out of cyber-space. Seriously, before I get to the new problem, I thought it would be valuable to disclose some of the following background leading up to the discovery of what kept the engine from firing.
I traced all pertinent wires to the VCM (the IC trigger wire (B)- the signal wire #9, and the CKP signal wire -#31 & ground wire -#28) None of these wires had any continuity to ground or to any other wire in the 4/ plug connectors going into the VCM (WHITE,BLUE,RED,BLACK).
I began, one at a time, disconnecting the various sensors, plugs, etc. in the FI system to check for spark at the secondary coil wire while cranking the engine ---to no avail. I noticed during the process a series of tiny "clicking" noises inside that plastic intake manifold every time I turn the key on or off (even with the injector harness plug disconnected) Normal?


...................................to be continued...............................................................

Part II (of 4)

I returned to what I believe to be the crux of the problem and it couldn't be put better than this, -(I wish I knew how to utilize the quote function in this forum) "What is triggering the ICM to be on all the time? With the transistor on all the time when the ignition is on or while cranking, the coil is going to be on all the time too. This theory would also explain why the PCM keeps setting the P1351 high volt circuit code" Discretesignals post #40 (And the waveform did verify this theory -one, continuous signal pattern, up to 4 volts, but never "breaking".)
I did re-check the disconnected plug at the ICM (A,B,C,D) and got the proper readings following the diagnostic chart previously posted by DS. (12 volts at (A and D) when key is in run position, good ground at (C), and 1-4 AC volts at (B) during cranking. The only remaining question concerns my reading of DC volts on (B) with the key off - .002 volts and with key on -- .004 volts. According to DS , "there should be no volts whatsoever". Is it possible that reading is just my volt/ohm meter goofing up?
Next I was lead to the clue that cornered the culprit in this nasty drama.

.....................................to be continued....................................................................

Part III (of 4)


I decided to check the voltage on the ICM by back-probing (with my volt meter on 12 volts DC) to see if I could observe a break in the signal. I started with the IC trigger wire (B) that comes from the VCM (A double mistake- First, I didn't disconnect the plug at the ICM, and second, I had it on the DC scale while testing an AC signal. Cf: DS post #10.) My friend's assertion is that that circuit is an AC signal to or from the VCM and the ICM and the CKP. So guess what happens during this improper test? It fires! I turned the engine off in two seconds and it got me to thinking. I just grounded the coil signal through the volt/ohm meter, so it could finally break the voltage and produce spark...which made me conclude that just because the connector on the ICM checks out when it is unplugged, it doesn't mean it is communicating with the terminals inside the ICM. Then, remembering the advice of Tom Greenleaf, Cf: post #29 and #30, I improvised a better connection to the ICM and...what do you know? It fires up immediately, every time, but now there is a new, different problem. It only runs about 10 seconds and then shuts down, -every time. What I am worried about is my jamming 12 volts DC down a 2 volt AC circuit and maybe I fried something.

.......................................to be continued........................................................

Part IV (of 4)

Now, sheesh, I have a different challenge, - what fun. It seemed to me that the fuel pump was working in the crank and run position -which makes me ponder why it immediately cuts out, (fuel or spark?) It sounds like I have solved one issue only to have created another one. What did I forget to do? I still haven't bolted the computer back in yet in case I need to retrieve it. And there was a procedure I was suppose to go through with the VCM once I get the engine running consistently. I suppose I will have to borrow my friend's scanner tool again to see if I am getting any new trouble codes. (Right, not the Vantage diagnostic tool, -thank you HT, I am a glutton when it comes to correction.) After following this sorry saga anyone have any ideas?, poignant comments?, wild guesses?,...............revelations?..............jokes?

Do you have a fuel pressure gauge attached to see if the pressure drops out before it dies. Does it restart after it dies?

You still have that oscilloscope? Does your buddy know how to use it? That scope can find out what is dropping out to make the engine quit. You just have to know how to use it and where to hook it.

I'm on it tomorrow! My buddy does have said tools and know-how and will be willing to look into this. That would be the scanner tool now, or the Vantage tool? He suggested I just hot wire the fuel pump to be on all the time, after the relay, to determine the fuel/spark question. It does restart immediately -each time after it dies. Thanks again for all your support. (I'll check back as soon as I've got more info.) B-1

im sorry after reading this thread "what was the exact problem"? vac leak? security issue? coil ground? bad wire? what?

Unfortunately this is one of the biggest problem here.....Poster will not comeback & close a thread with either the fix or I give up....

If you are having a problem go ahead a start a new thread & we see if we can help you out......We don't add new problems to old threads, it gets too confusing....

I guess we were ignoring the security warning on the dash all this time.

Passlock shouldn't kill the ignition, just the injectors. Passlock also won't kill the engine while it is running. Only disables the engine from starting.

You have all sorts of goofy things going on with those connectors. I honestly still don't understand the P1351 code showing up because of a connector problem, but that looks to be resolved.

Crankshaft variation doesn't learn by driving it around. You have to use a high end scan tool to do a crank learn. If you don't do the crank learn, the PCM will disable the misfire monitor or give you the wrong cylinders that are missing if it does end up missing.

Glad to see you got it going and good luck with your inspection.

Might also want to stop the leaking on the pcm.

this is the longest damn post I have ever seen. Glad to see you followed instructions and have a running engine. I'm sure we will see you back.

Yep - site record I'm near sure. Glad thru all this there was such positive results. Thanks for the kind words for the techs and the site. I just did the heavy looking on. These guys are sharp no question.

Best of luck with the emissions test,

Tom

b_oneself - did you hit "post reply" before writing anything or was that part of April Fools Day antics?

If by mistake you can change in your settings to see what you posted right after and edit your own from there if a mistake.

BTW, I think this thread has set a site record for # of posts! No problem. The regulars and certainly all mods know how to deal with it,

The one you can Google with kitty as an avatar just to prove I'm not wrapped real tight!

Tom





PS: Go ahead and swat that bug - I almost did first time I saw that one..........

Tom,
Alas, I did write a lengthy report last night (2:00 AM EDT) and when I went to post it I must have hit the wrong "button". (Maybe because it was a new day -April 2 ???) Rats, I wish I knew how to "check my settings" and see if I can pull it back up. No, that wasn't part of the April Fool's gag. I guess the joke's on me. I suppose I'm just going to have to re-type everything -and there was a lot to mention!

Double rats!,
I just re-typed and re-posted my lengthy report and it was wiped out again! I know I was logged on like I was last night but when I pushed "post reply" it went back to the log-in page. When I logged in again my response was gone (an hour and half of typing). This time my computer followed with the message A fatal error has occurred: unable to post with a GET method at /home/carjunky............................................/post/write.pm line 915.

Reboot your computer and try again. Copy the answer before hitting post.

Thanks, you guys,
I will re-boot, and re-post, and attempt to save. (my problem is I don't know how to paste it back in later if it does get lost) So I would like to send it via several separate, consecutive posts. Please be patient with me. -I am so lame in the digital world. But I really do need help with the present roadblock.

Look up top where it says "edit profile" and you can make changes there. Site's software can screw up itself also. I didn't check yours but suggest leaving your email address hidden as about anyone could click on your user name and get it then who knows.

Nobody, even moderators can dig out your registered email address and spammers do get in here but we remove them asap so if you ever search around some may say that it doesn't exist so one of us took it out and sorry if you get a notice of a reply made and nothing there but it just meant it was a junk post not welcomed.

You have a lot of posts on this thread and if annoying can click on "stop watching" on the notice you get. I don't control anything here but will try to make old threads automatically be just locked as archived to stop notices on a done thread,

Carry on,

Tom

I guess you exorcised the demons. You guys aren't pulling my chain are ya? It is April 1st

So then is it necessary to pull the master, the metal brake lines, the power steering fluid reservoir, -more? before one can get at the VCM. Now that you have clarified the location I'm trying to see about finding that particular ground on the unit you mentioned previously. I obviously did not see it before. (as a last ditch effort to avoid this ultimate verdict about the VCM). Thanks, Bob

Finally, a minor (or maybe even major) breakthrough! This post concerns the confusion arising over the issue of whether or not I was getting 12 volts at the (D) terminal of the ICM. And here's to the value of double-checking -or repetitive validating in the scientific method: OK, so here's the deal. Following all the procedures carefully and by the book I check the (D) terminal on the ICM and get nothing. I repeat the process and now I get 12 volts. I repeat the test many times over, sometimes getting 12 volts, sometimes nothing. I realize eventually that connector on the coil definitely has a way loose connection. (My harness has only 2 wires (A & C) -no (B) because there is no tachometer in the vehicle. Even though the two wires are snugly in the plastic (no movement at all), there is clearly much slop between the male & female when plugged in - meaning either the posts (pins) in the new coil are a slightly smaller dimension, or my female connector plug (receptacle) is worn out, ie., the hole is too big. I'll work on resolving that loose fit next chance I get. I can imagine why this is preventing the engine from getting spark. Is there any chance it could also be the cause of my P1351 trouble code? It would be great to have this van starting again.

If you found a sloppy connection like that I'd concentrate on that. Your call and I'm not looking at this connection but there are things you can do to make them work dependably depending on just how they are made - things like torquing/twisting the male or a gentle squish on a female or take very small screwdriver and see if it can be persuaded without harming it,

T

i see, lol im still learning thankyou for clearing all that up though DS

Oh boy. I don't know if you recognize this thread being related to that one entitled "power problem" from back in early Jan. That was the one where you (Hammer Time) walked me through a long process of diagnosing, in the end, a bad fuel pump (because I kept jumping to conclusions prematurely) Naturally, since I did eventually replace the pump -which corrected the problem *thank-you very much*, and because I observed the pump currently working during pre-load and in starting mode I didn't even consider the possibility of a fuel problem. Plus, I injected starter fluid into the intake boot at the air cleaner and still no combustion. Nevertheless, fuel pressure is a fair question -if only to eliminate that fundamental concern (min. 55psi). So I'll go borrow that "known working" fuel pressure tester and confirm I've got enough. Still, I am wondering if that P1351 code isn't spark related. Despite my attempt to eliminate the PO171 & PO174 -(and you pointed to the vacuum leaks I found), this engine has been starting and running great ever since the fuel pump fixed the "power problem" in Jan. It suddenly stopped starting yesterday. To be continued...when there is more info/ideas

You probably don't have any spark, since spraying the intake didn't make the engine start, pop, or do anything.

If your getting that P1351 code which sets when the engine is cranking all the time, that probably means that the PCM can't signal the ignition control module or the ignition control module died. Testing would verify that. You could have a defective ignition control module even though it is a replacement. The ignition control module also needs a light coat of thermal paste when you screw it to the heat sink. You don't paste it and it will burn up or fail early.

No ignition module activity, power or ground missing to the module, open in primary circuit from the coil, or no trigger signal to the module from the PCM and you won't have any spark. Of course, an open in the primary circuit from the coil won't cause a P1351.

Gotcha. That's where I think I should go next. (I did the thermal paste thing, but maybe I did it wrong or maybe the part is defective?) Thanks for the suggestions. Both of you, -all of you. What a great forum!

My fuel pressure question was triggered by the lean codes

Discrete One and Hammer Time,
I should also like to add that we did replace the dist. module, the coil, and the pick-up in the dist. at the same time ( just previous to) the corrective repair, i.e., the fuel pump. (We also replaced wiring to the fuse box "relay station", the fuel pump relay, the fuel pressure regulator, spark plugs, upstream O/2 sensors, checked for blockage in the exhaust & more - cf. "power problem" (Jan. 6, 2012) I'm going to try and carefully follow the advice I am gratefully receiving from you two. I'm also trying to apply a little logic and add some common sense to the puzzle at present, and given the limitations of resources.(I do have a good volt-om meter)
Much appreciated, Bob

Haven't heard of a crank sensor causing a stall only at idle. Don't really understand why using the spare key would solve your issue. The ignition key or key less transmitter has a transponder, but that is used by the immobilizer and shouldn't cause your data bus to go down, stalling, or P0011 code to show up.

Did you have any aftermarket equipment installed or something hanging off the key chain that produced a radio signal or could cause EMI? Did this stalling issue just show up one day or has it been doing this for a while? Maybe it is just a coincidence and the problem is intermittent?

Actually. I do have an "aftermarket" wiring kit that allowed me to upgrade the stock radio to the OEM navigation package. It's been in my vehicle for a year and half though with no previous problems.

I already shelled out $600 to a local repair shop and hate to take it back to the dealer unless I can figure out the reason why the alternate key has negated the previous problem.

Very strange. The 11's are still kind of new to show up in the independents, so haven't run into that situation.

The P0011 is a camshaft sensor performance code. It doesn't necessary mean the sensor is faulty or has an electrical issue. It just means the computer was expecting the camshaft to be at a certain position and it wasn't.

The ECM detects the difference between the desired camshaft position angle and the actual camshaft position angle is greater than 5 degrees for greater 2.5 s.

This does have variable valve timing it is possible for the engine to stall or run really bad if the camshaft wasn't at the right position at idle speeds. Of course, that code may of had nothing to do with it stalling, but there is always a possibility. Looking at freeze frame data when it coded may have given some clues. Did the code ever come back?

Was there anything on the key chain with the original key? Just strange that the data bus was affected by this. I guess time will tell.

The code has not returned as of today. And as far as I can tell both keys are identical.

Broke down and made an appointment to have dealer look at it. I'll advise when I get results.

Thanks to all who have brainstormed this conundrum!