2.8 Missfire - Lesson about spark plug torque (long but worth the read)
07-07-2005, 07:29 PM
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2.8 Missfire - Lesson about spark plug torque (long but worth the read)
'98 A4 Avant 2.8 5 speed 61K miles
Missfire at 1000 to 1500 RPM under moderate load. Check engine light came on. I had no time to mess with it. Day before a 700 mile drive from Denver CO to Bozeman MT with wife and 2 small children. Dealer diagnosed as coil pack failure $340 to replace. Still missed drove back dealer and replaced 2 spark plug wires. Still missed but not as bad. Drove to Bozeman with no problem but while driving into town it missed badly and threw CEL. Tuesday after the 4th took it to Dick Walter Audi in Bozeman. Tech came out and asked me into the bay. Had the engine cover off and showed me what looked like webs in the dust around the coils where they connect to the coil frame. He said that the webs were from high voltage trying to find a ground. He said the spark plugs were not grounding. He pulled one of the Bosch +4s I had installed at 60K and checked their condition. He agreed they were new. He then pulled all 6 plug wires and torqued the plugs to 14 lbs. He put it together and the service manager and I took it for a ride and what the tech did fixed it. I gladly paid a $142 for the diagnosis and 1 spark plug wire he replaced as a precaution. The tech was an older guy with a heavy accent and enough experence to interpet marks in the dust on my coils. I know the heads are alloy so I tighten the plugs to where I feel the washer crush and the resitance increases - my mistake. I have a torque wrench. Prestige Audi in Denver was surprised and said they don't torque plugs but they would start. Bottom line - it cost me a lot of time and worry and $500 to change my own plugs. I hope I don't go broke before I learn enough about this car to not screw up.
Missfire at 1000 to 1500 RPM under moderate load. Check engine light came on. I had no time to mess with it. Day before a 700 mile drive from Denver CO to Bozeman MT with wife and 2 small children. Dealer diagnosed as coil pack failure $340 to replace. Still missed drove back dealer and replaced 2 spark plug wires. Still missed but not as bad. Drove to Bozeman with no problem but while driving into town it missed badly and threw CEL. Tuesday after the 4th took it to Dick Walter Audi in Bozeman. Tech came out and asked me into the bay. Had the engine cover off and showed me what looked like webs in the dust around the coils where they connect to the coil frame. He said that the webs were from high voltage trying to find a ground. He said the spark plugs were not grounding. He pulled one of the Bosch +4s I had installed at 60K and checked their condition. He agreed they were new. He then pulled all 6 plug wires and torqued the plugs to 14 lbs. He put it together and the service manager and I took it for a ride and what the tech did fixed it. I gladly paid a $142 for the diagnosis and 1 spark plug wire he replaced as a precaution. The tech was an older guy with a heavy accent and enough experence to interpet marks in the dust on my coils. I know the heads are alloy so I tighten the plugs to where I feel the washer crush and the resitance increases - my mistake. I have a torque wrench. Prestige Audi in Denver was surprised and said they don't torque plugs but they would start. Bottom line - it cost me a lot of time and worry and $500 to change my own plugs. I hope I don't go broke before I learn enough about this car to not screw up.
07-07-2005, 09:13 PM
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is there something different with mine or something?,mine has a hitachi coilpack on the top near ...
the front of the engine and standard spark plug wires on each plug. you have a coil pack on each plug like the 1.8's?
mine is a 12v V6
mine is a 12v V6
