SVT232V6
Member
Asking for help because I can’t seem to understand what I believe is an intermittent misfire.
2004 3.8L V6 176K. I have 2 codes:
P0316 Misfire Detected On Startup(First 1000 Revolutions)
P0304 Cylinder 4 Misfire Detected
I have a spare donor parts car, so I’ve changed out the:
-spark plug
-spark plug wire
-ignition coil
-fuel injector
No change. I replaced the Y-pipe and crank sensor and the car ran perfectly for several days on short trips around town. Then it started missing again after a longer trip to the city. I experimented a little to recreate the misfire circumstance. If I start up the car cold and let it be, it will idle fine. If I give it throttle, it will rev up, then the idle will go very low(~500rpms) and nearly stall, then start missing consistently at idle. If I pull the number 4 spark plug wire from the coil, the miss gets worse. The idle improves after putting the plug wire back on and the miss will get better. If I then shut off the car and immediately restart it, there’s still a misfire but it’s no longer as bad. I’m confused and lost. Open to suggestions and further testing! I don’t know if anything that will cause or worsen a misfire after getting on the gas. What else am I missing?
2004 3.8L V6 176K. I have 2 codes:
P0316 Misfire Detected On Startup(First 1000 Revolutions)
P0304 Cylinder 4 Misfire Detected
I have a spare donor parts car, so I’ve changed out the:
-spark plug
-spark plug wire
-ignition coil
-fuel injector
No change. I replaced the Y-pipe and crank sensor and the car ran perfectly for several days on short trips around town. Then it started missing again after a longer trip to the city. I experimented a little to recreate the misfire circumstance. If I start up the car cold and let it be, it will idle fine. If I give it throttle, it will rev up, then the idle will go very low(~500rpms) and nearly stall, then start missing consistently at idle. If I pull the number 4 spark plug wire from the coil, the miss gets worse. The idle improves after putting the plug wire back on and the miss will get better. If I then shut off the car and immediately restart it, there’s still a misfire but it’s no longer as bad. I’m confused and lost. Open to suggestions and further testing! I don’t know if anything that will cause or worsen a misfire after getting on the gas. What else am I missing?
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