Random mis-fire HELP!!!
Thread Starter
New Member
Joined: Dec 2004
Posts: 10
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Random mis-fire HELP!!!
1996 A4Q 2.8 Manuel
I've had a check engine light come on and off for 2 years now. The code read miss-fire cylinder #1 then Random Multiple miss-fire.
I've tried every thing and my mechanical has given up. The car has plenty of power but runs a little rough. It idles at 750 (a little low). some times it takes a couple of cranks to get it started when cold. The spark plugs seam to indicate a slightly lean mix. And I get a slight knocking on heavy loads (up hill high gear). the car never stalls. I've changed the following:
Coil Pack, wires, plugs
Timing belt
O sensor
Fuel filter and pump.
Right side cylinder head (twice used)
Ignition module (used)
I did a quick check for a vacuum leaks on the top but found nothing. I know it sounds silly, but the light actually started coming on after I had the clutch and flywheel changed. Also the light won't come on if I run the car with the A/C on (raises idle).
The car has a S/S exhaust and K&N filter but light came on before they were installed.
Any Ideas, I'm dispirit
I've had a check engine light come on and off for 2 years now. The code read miss-fire cylinder #1 then Random Multiple miss-fire.
I've tried every thing and my mechanical has given up. The car has plenty of power but runs a little rough. It idles at 750 (a little low). some times it takes a couple of cranks to get it started when cold. The spark plugs seam to indicate a slightly lean mix. And I get a slight knocking on heavy loads (up hill high gear). the car never stalls. I've changed the following:
Coil Pack, wires, plugs
Timing belt
O sensor
Fuel filter and pump.
Right side cylinder head (twice used)
Ignition module (used)
I did a quick check for a vacuum leaks on the top but found nothing. I know it sounds silly, but the light actually started coming on after I had the clutch and flywheel changed. Also the light won't come on if I run the car with the A/C on (raises idle).
The car has a S/S exhaust and K&N filter but light came on before they were installed.
Any Ideas, I'm dispirit
Thread Starter
New Member
Joined: Dec 2004
Posts: 10
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Re: UM.... codes?
This is exactly what comes out on the ticket. The 072 at the end of the code some times comes up as 93 or 92 and 120 (I have many tickets)
8D0906266B 2.8l V6/2V MPI OBD2 D01
Coding 01201 WSC 75100
16685 po301 072
Cyl.1
Misfire Detected
16686 po302 072
Cyl.2
Misfire Detected
16687 po303 072
Cyl.3
Misfire Detected
16684 po300 072
Random/Multiple Cylinder
Misfire Detected
8D0906266B 2.8l V6/2V MPI OBD2 D01
Coding 01201 WSC 75100
16685 po301 072
Cyl.1
Misfire Detected
16686 po302 072
Cyl.2
Misfire Detected
16687 po303 072
Cyl.3
Misfire Detected
16684 po300 072
Random/Multiple Cylinder
Misfire Detected
Thread Starter
New Member
Joined: Dec 2004
Posts: 10
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Re: has your mechanic verified the timing's correct? ie, with a light?
I wouldn't even know where to put the timing light on the car. Everything is set by the computer.
I have to believe the timing is OK because the timing belt has been re-installed numerous times. There is no other way to adjust the timing as far as I know.
I have to believe the timing is OK because the timing belt has been re-installed numerous times. There is no other way to adjust the timing as far as I know.
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From: Dallas TX
Depends upon how bad the fuel pressure problem is.
The fact that you may be running a bit on the lean side may be an indication of a fuel system issue that is mostly apparent at low rpms.
Injectors that are dirty and missing will throw those same codes. Try a good dose of techron and a long high speed drive.
Injectors that are dirty and missing will throw those same codes. Try a good dose of techron and a long high speed drive.