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The car: 1986 Fiero GT 4 speed with 2005 Chevrolet Equinox 3400 V6 (LNJ) swap using 1998 3400 (LA1) controls. Swapped to 24x crank trigger wheel (harmonic balancer) and installed external 7x crank trigger wheel. 7X, 24x, and cam position sensors were all brand new when I did the engine swap in 2011.
Car has been slowing misfiring worse and worse since before winter. Did a clutch and exhaust job over winter with the engine out, finally got it back together but now after about 20-30 miles of test drive it is misfiring bad enough to barely be able to cruise when below 3k rpms. Car starts bucking when given throttle. Anything over about 3k no big deal, car runs great.
Based on past experience the issue is with one of the crank sensors.
codes are:
P0300 (multiple cylinder misfire...no surprise here)
P0336 (crankshaft position sensor A circuit Range/Performance)
So my first thought is, have I messed up the timing by accidentally adjusting the 7X trigger location? I adjusted the 7x sensor timing. It was 1 degree off, set it back to zero. Cleared the codes, let it idle for a bit while I put the wheel and tire back on and moved cars around the driveway before going for a short test drive. Car doesn't really drive any differently. This leads me to the 24x sensor?
If the 7x sensor isn't telling the computer that the crank is out of sync with the 24x and cam sensor, and the sensors are all new, I think I'm leading toward a wiring issue with one of these sensors. The 7x wire is just a plug and play twisted wire from the sensor to the coil packs (ICM.) Getting into the 24x and cam sensor wires is going to be a chore so I thought I would ask you all for opinions on what might cause this misfire and crank code.
thought?
Car has been slowing misfiring worse and worse since before winter. Did a clutch and exhaust job over winter with the engine out, finally got it back together but now after about 20-30 miles of test drive it is misfiring bad enough to barely be able to cruise when below 3k rpms. Car starts bucking when given throttle. Anything over about 3k no big deal, car runs great.
Based on past experience the issue is with one of the crank sensors.
codes are:
P0300 (multiple cylinder misfire...no surprise here)
P0336 (crankshaft position sensor A circuit Range/Performance)
So my first thought is, have I messed up the timing by accidentally adjusting the 7X trigger location? I adjusted the 7x sensor timing. It was 1 degree off, set it back to zero. Cleared the codes, let it idle for a bit while I put the wheel and tire back on and moved cars around the driveway before going for a short test drive. Car doesn't really drive any differently. This leads me to the 24x sensor?
If the 7x sensor isn't telling the computer that the crank is out of sync with the 24x and cam sensor, and the sensors are all new, I think I'm leading toward a wiring issue with one of these sensors. The 7x wire is just a plug and play twisted wire from the sensor to the coil packs (ICM.) Getting into the 24x and cam sensor wires is going to be a chore so I thought I would ask you all for opinions on what might cause this misfire and crank code.
thought?
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