LQ4 missfire
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Joined: Aug 2008
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LQ4 missfire i have a 2001 2500hd, and the motor has a bad misfire it shakes and won't idle. i ran a diagnostic check and it said #8 cylinder misfire p0308, so i switched the #6 coil and the #8 and the computer said p0300 random misfire detection, is it possible the crank sensor is bad? the truck is completely stock, some body else looked at it and said the fuel rail was bad, that to me makes little sense please give me some advice thank you.
The fuel rails on the trucks have problems with the coating flaking off the inside and plugging the injectors. So the bad fuel rail is highly likely. Try taking the rails and injectors off and clean them with some carb cleaner and compressed air. If the miss goes away you have found your problem, but it will most likely happen again if you don't change the rail.
