Has this happened to anyone!
essikr
03-20-2006, 07:43 AM
2001 GP,GT 3.8 (posted problem before)
Symptoms: Engine misfire and backfireing as if timing is off.Popping can be heard in the exhaust.Happens randomly with car hot or cold,driving or idling.The engine light has come on and flashed at times.The codes that came up are P0300,P1361,P1362. The engine coolant temp will go up while it is misfiring (it goes back down when it clears).If the ignition is turned off and restarted the problem goes away and the service light goes out. If the car sits for several days it usually takes two to three days for it to act up :screwy: .
The following items have been replaced or swapped with known good parts.
Spark plugs, plug wires,ICM and wiring harness,camshaft sensor,PCM,battery ,all grounds cleaned and tightened,catalytic converter(when the converter was replaced the Pontiac garage could not find the problem ,it would not do it),fuel filter,tested fuel pump pressure, dielectric grease put on injector connections,cleaned MAF sensor,transmission was replaced 9 months ago, coolant level checked and stays normal. I have been trying to find the problem on my daughters car for months now,it's a quest!!! Can anyone help?:screwy:
Stumped Old Retired Pontiac Service Craftsman
Symptoms: Engine misfire and backfireing as if timing is off.Popping can be heard in the exhaust.Happens randomly with car hot or cold,driving or idling.The engine light has come on and flashed at times.The codes that came up are P0300,P1361,P1362. The engine coolant temp will go up while it is misfiring (it goes back down when it clears).If the ignition is turned off and restarted the problem goes away and the service light goes out. If the car sits for several days it usually takes two to three days for it to act up :screwy: .
The following items have been replaced or swapped with known good parts.
Spark plugs, plug wires,ICM and wiring harness,camshaft sensor,PCM,battery ,all grounds cleaned and tightened,catalytic converter(when the converter was replaced the Pontiac garage could not find the problem ,it would not do it),fuel filter,tested fuel pump pressure, dielectric grease put on injector connections,cleaned MAF sensor,transmission was replaced 9 months ago, coolant level checked and stays normal. I have been trying to find the problem on my daughters car for months now,it's a quest!!! Can anyone help?:screwy:
Stumped Old Retired Pontiac Service Craftsman
fst100
03-20-2006, 08:35 AM
what brand of plugs and wires are you using as well as other brand products? you also mentioned you changed the 'PCM'? to what, another stock pcm? if you want goto clubgp.com and address your issues there under the problems and issue forum.
BNaylor
03-20-2006, 08:51 AM
I see you haven't given up on the problem.
Concentrate on the second two codes P1381 & P1362 and not the random misfire 300 code.
The bypass circuit is either shorted or open for the ignition control module (ICM) or the ICM is not properly processing the 3X pulses from the crank position sensor.
Basically the PCM is not getting the required signals it needs for fuel and spark advance calculations.
At engine start, the ICM controls spark advance (by-pass mode). When the 3X signal is recognized by the PCM, it applies 5 volts to bypass the circuit, commanding the ICM to switch from ICM control of spark advance to PCM mode (IC Mode).
You have either an open or short in the wiring going from the crank position sensor to the ignition control module or wiring problem from the ICM to the PCM. As to replaceable parts it could be either a crank position sensor or ignition control module.
BTW - If you get an ICM tested at Autozone, it is worthless because they cannot check this specific part of the circuit. Good luck!
Concentrate on the second two codes P1381 & P1362 and not the random misfire 300 code.
The bypass circuit is either shorted or open for the ignition control module (ICM) or the ICM is not properly processing the 3X pulses from the crank position sensor.
Basically the PCM is not getting the required signals it needs for fuel and spark advance calculations.
At engine start, the ICM controls spark advance (by-pass mode). When the 3X signal is recognized by the PCM, it applies 5 volts to bypass the circuit, commanding the ICM to switch from ICM control of spark advance to PCM mode (IC Mode).
You have either an open or short in the wiring going from the crank position sensor to the ignition control module or wiring problem from the ICM to the PCM. As to replaceable parts it could be either a crank position sensor or ignition control module.
BTW - If you get an ICM tested at Autozone, it is worthless because they cannot check this specific part of the circuit. Good luck!
BNaylor
03-20-2006, 08:55 AM
if you want goto clubgp.com and address your issues there under the problems and issue forum.
FST100...lol :lol: Club Med? Thats a good one. He has come to the right place to get his problem resolved.
FST100...lol :lol: Club Med? Thats a good one. He has come to the right place to get his problem resolved.
chevelle_6969
03-20-2006, 09:04 AM
YOu know this happened to our 97 grand prix and the only thing that was wrong is the back plug wasn't pushed in tight enough. When we put a different motor in we some how hit the plug closest to driver side and it wasn't in tight. We took it to a pontiac service place and they told us we needed new plugs. We paid them over a 100 bucks to tell us this and my wife grabbed the last plug wire only to find out it wasn't on all the way.
Hope this helps
Hope this helps
BNaylor
03-20-2006, 09:23 AM
YOu know this happened to our 97 grand prix and the only thing that was wrong is the back plug wasn't pushed in tight enough. When we put a different motor in we some how hit the plug closest to driver side and it wasn't in tight. We took it to a pontiac service place and they told us we needed new plugs. We paid them over a 100 bucks to tell us this and my wife grabbed the last plug wire only to find out it wasn't on all the way.
Hope this helps
Was your problem in conjunction with the P1381 & P1362 DTC error codes? Until those two specific codes are troubleshot and repaired you can change spark plugs all day. He'll still have the same problem.
Hope this helps
Was your problem in conjunction with the P1381 & P1362 DTC error codes? Until those two specific codes are troubleshot and repaired you can change spark plugs all day. He'll still have the same problem.
essikr
03-20-2006, 01:52 PM
The ICM and the wiring from it to the sensors were swapped out.The parts came from a 2001 GP that ran fine. Did not change the cranksensor ,concerned about variation learn procedure for it.Could this sensor fail just occasionally(I do have one)? I have looked at the wiring from ICM to the PCM when I swapped the PCM out.If you think it's worth it I will seperate the wires from the harness and check them closely. What can possibly allow the car to run fine if you let it sit for days(actually I let it sit for 10 days then it ran fine for 4 days). Thanks for responding .Still trying but getting grayer every day.
BNaylor
03-20-2006, 02:30 PM
The ICM and the wiring from it to the sensors were swapped out.The parts came from a 2001 GP that ran fine. Did not change the cranksensor ,concerned about variation learn procedure for it.Could this sensor fail just occasionally(I do have one)? I have looked at the wiring from ICM to the PCM when I swapped the PCM out.If you think it's worth it I will seperate the wires from the harness and check them closely. What can possibly allow the car to run fine if you let it sit for days(actually I let it sit for 10 days then it ran fine for 4 days). Thanks for responding .Still trying but getting grayer every day.
Did the wiring include from the ICM to the crank angle position sensor and from the output of the ICM back to the PCM. I'd ohm everything out point to point with a ohmmeter per the service manual wiring diagrams. Also look for shorts referenced to ground. The PCM is sensing no input (open) or a short producing the P1361 & 1362 DTC error codes. Until the PCM can switch to IC mode you'll be stuck with the problem. You have nothing to lose at this time since you have changed everything else imagineable. I believe you are on the 2nd month with the problem? You're symptoms are similar to an intermittent CKPS without the engine stall or cutoff. The 18X pulses out of the CKPS could be noisy or distorted. It is a Hall Effects sensor. You could verify this with an oscilloscope. Good luck!
Here is the procedure to do a CKPS.
http://mykidz.net/GTP/CrankPosSensor.shtml
Did the wiring include from the ICM to the crank angle position sensor and from the output of the ICM back to the PCM. I'd ohm everything out point to point with a ohmmeter per the service manual wiring diagrams. Also look for shorts referenced to ground. The PCM is sensing no input (open) or a short producing the P1361 & 1362 DTC error codes. Until the PCM can switch to IC mode you'll be stuck with the problem. You have nothing to lose at this time since you have changed everything else imagineable. I believe you are on the 2nd month with the problem? You're symptoms are similar to an intermittent CKPS without the engine stall or cutoff. The 18X pulses out of the CKPS could be noisy or distorted. It is a Hall Effects sensor. You could verify this with an oscilloscope. Good luck!
Here is the procedure to do a CKPS.
http://mykidz.net/GTP/CrankPosSensor.shtml
essikr
03-20-2006, 04:41 PM
The engine does stall at times . I did not get the harness from the ICM to the PCM .From the plug by the ICM the wiring is in the main harness. Thanks for the procedure on the CKPS ,from what I'm reading this could cause an intermittent problem ???? Going to change it out ,I have one. Don't have the wiring diagrams but I should be able to read whether the wires from the plug to the PCM are open or grounded.
BNaylor
03-20-2006, 05:13 PM
Thanks for the procedure on the CKPS ,from what I'm reading this could cause an intermittent problem ???? Going to change it out ,I have one.
Absolutely. Most of the CKPS problems I've encountered are intermittent. Stalling is a classic sign. On a few occasions you may get a trac off light after stall and the tach will abruptly drop to zero about a split second before you notice the engine has stalled out.
When I get a chance later I may be able to provide the pins numbers and wire color coding from the ICM to PCM. Or send me a PM and I'll send you the pertinent page. Good luck!
Absolutely. Most of the CKPS problems I've encountered are intermittent. Stalling is a classic sign. On a few occasions you may get a trac off light after stall and the tach will abruptly drop to zero about a split second before you notice the engine has stalled out.
When I get a chance later I may be able to provide the pins numbers and wire color coding from the ICM to PCM. Or send me a PM and I'll send you the pertinent page. Good luck!
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