car died on me while driving
11-01-2008, 11:59 PM
#32
Nordschleife Master
I will be driving my 88 to DC from Richmond tomorrow morning, give me a call at (804) 248-1712 if you need help, I can stop by on my way back down...Not a whole lot of 944 knowledge, but I might be persuaded to bring along my factory service manual set, and my tool box.....my AFM works fine, we could swap to see if it is your problem.... My money is on bad reference sensor, plug wires, or cracked hose in the system somewhere.... Call me, I love working on my car, someone else's just makes it that much more fun....
11-02-2008, 09:33 AM
#33
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Well it could be a bad AFM but that would not make it run on three cylinders. If indeed the injectors were tested, which I kinda doubt, and one of them is cutting out sometimes it has to be the injector harness wiring or the Speed/Ref sensors, or the wiring related to them (combined with some bad luck that makes the fault appear only when one particular injector is firing.)
If it's just running badly, running pig rich, it's probably something like the FPR or damper that is leaking and that is easy enough to diagnose.
I personally would forget everything you learned from this mechanic and start over. The DME relay is a very common failure and replacing it seems to have gotten you running so my first guess would be the mechanic goofed something up before replacing the DME relay (or afterwards because he has a boat payment to make.)
-Joel.
If it's just running badly, running pig rich, it's probably something like the FPR or damper that is leaking and that is easy enough to diagnose.
I personally would forget everything you learned from this mechanic and start over. The DME relay is a very common failure and replacing it seems to have gotten you running so my first guess would be the mechanic goofed something up before replacing the DME relay (or afterwards because he has a boat payment to make.)
-Joel.
11-02-2008, 09:47 AM
#34
Team Owner
yeah tak about coincidences , you happen to have your dme relay and something else go bad at the same time ? NOT
it all depends too how he tested the injectors. if you are in doubt swap the injector with another cylider and see if the problem follows. Easy troubleshooting step. Go from there.
it all depends too how he tested the injectors. if you are in doubt swap the injector with another cylider and see if the problem follows. Easy troubleshooting step. Go from there.
11-03-2008, 07:35 AM
#36
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yeah tak about coincidences , you happen to have your dme relay and something else go bad at the same time ? NOT
it all depends too how he tested the injectors. if you are in doubt swap the injector with another cylider and see if the problem follows. Easy troubleshooting step. Go from there.
it all depends too how he tested the injectors. if you are in doubt swap the injector with another cylider and see if the problem follows. Easy troubleshooting step. Go from there.
Well it could be a bad AFM but that would not make it run on three cylinders. If indeed the injectors were tested, which I kinda doubt, and one of them is cutting out sometimes it has to be the injector harness wiring or the Speed/Ref sensors, or the wiring related to them (combined with some bad luck that makes the fault appear only when one particular injector is firing.)
If it's just running badly, running pig rich, it's probably something like the FPR or damper that is leaking and that is easy enough to diagnose.
"how would I diagnose this"
I personally would forget everything you learned from this mechanic and start over. The DME relay is a very common failure and replacing it seems to have gotten you running so my first guess would be the mechanic goofed something up before replacing the DME relay (or afterwards because he has a boat payment to make.)
-Joel.
If it's just running badly, running pig rich, it's probably something like the FPR or damper that is leaking and that is easy enough to diagnose.
"how would I diagnose this"
I personally would forget everything you learned from this mechanic and start over. The DME relay is a very common failure and replacing it seems to have gotten you running so my first guess would be the mechanic goofed something up before replacing the DME relay (or afterwards because he has a boat payment to make.)
-Joel.
I will be driving my 88 to DC from Richmond tomorrow morning, give me a call at (804) 248-1712 if you need help, I can stop by on my way back down...Not a whole lot of 944 knowledge, but I might be persuaded to bring along my factory service manual set, and my tool box.....my AFM works fine, we could swap to see if it is your problem.... My money is on bad reference sensor, plug wires, or cracked hose in the system somewhere.... Call me, I love working on my car, someone else's just makes it that much more fun....
Pm will be sent
11-03-2008, 04:07 PM
#37
Got Nothin'
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Still sounds like the FPR..
If it runs horribly rough, and rich when cold. Try this. Pull an injector wire and see if the idle smoothes out. That would confirm the FPR.
If it runs horribly rough, and rich when cold. Try this. Pull an injector wire and see if the idle smoothes out. That would confirm the FPR.
11-03-2008, 07:58 PM
#38
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do i pull the injector wire from any injector or just the one that is cutting off randomly? If i pull the injector wire and the idle smooths out, can this also be a bad reference sensor.
11-03-2008, 07:59 PM
#39
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Well it could be a bad AFM but that would not make it run on three cylinders. If indeed the injectors were tested, which I kinda doubt, and one of them is cutting out sometimes it has to be the injector harness wiring or the Speed/Ref sensors, or the wiring related to them (combined with some bad luck that makes the fault appear only when one particular injector is firing.)
If it's just running badly, running pig rich, it's probably something like the FPR or damper that is leaking and that is easy enough to diagnose.
I personally would forget everything you learned from this mechanic and start over. The DME relay is a very common failure and replacing it seems to have gotten you running so my first guess would be the mechanic goofed something up before replacing the DME relay (or afterwards because he has a boat payment to make.)
-Joel.
If it's just running badly, running pig rich, it's probably something like the FPR or damper that is leaking and that is easy enough to diagnose.
I personally would forget everything you learned from this mechanic and start over. The DME relay is a very common failure and replacing it seems to have gotten you running so my first guess would be the mechanic goofed something up before replacing the DME relay (or afterwards because he has a boat payment to make.)
-Joel.
11-04-2008, 09:35 AM
#41
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A bad ref sensor will not let the car start. It really has nothing to do with the idle, as far as I know.
11-04-2008, 06:26 PM
#42
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ok new update i misunderstood him! it only runs when on three cylinders. if all injectors are plugged in then it will barely start. if any injector is pulled out then it will start but run S****Y! it almost reminds me of a misfire i had earlier. the car feels like its puttering. So i guess this is a bad FPR or damper which one should i get? please respond ASAP
11-04-2008, 07:46 PM
#44
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11-04-2008, 09:10 PM
#45
Lazer Beam Shooter
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The damper doesn't regulate much fuel at all. It actually just dampens vibrations from the fuel rail.
For what its worth, I dont have a damper on my 951. Id replace the fuel pressure regulator
For what its worth, I dont have a damper on my 951. Id replace the fuel pressure regulator