Misfire is it spark or Fuel? (fixed)
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From: Neligh, Nebraska

Ok, so my bonnie threw a Misfire code and its cylinder 2 and it is very noticeable. The problem is, the misfire only happens when the Supercharger is in positive boost. What is going on here? Gunner thinks its Fuel injector. I'm inclined to agree, but I have a feeling its not that. I replaced the spark plug wires this morning and it is running better, the miss isn't as bad but its still there, only when the */c kicks in. I have injectors on the way, but I'd like to make sure it'* not something else...
Do you have a mechanics sthescope or a volt meter?You can pull the plug for that injector and stick your meter to it and see if the voltage ''pulses'' while cranking the engine and also while running with all injectors plugged in poke it with a sthescope to see if its clicking
Thread Starter
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From: Neligh, Nebraska

I do have the volt meter but it'* with my dad so it'* going to have to wait til he gets home from work. I also forgot to mention that it doesn't misfire when you rev in park, only when its in Neutral or in gear and then it'* a different rpm range for every gear. Generally though it is around 2k in 1st and 2nd gear and just over 3k in 3rd
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From: Neligh, Nebraska

Have a new problem to that may have contributed to the existing one. The copper door in the filler neck will not come completely shut at all, it'* almost like someone forced it open with something other than the gas nozzle at the station. There has never been an issue like that with this car and I just found it yesterday when I went to put fuel injector cleaner in the tank. I am starting to get a notion that someone may have put something in the gas tank. Also found that the door is not locking when the car is locked.
Joined: May 2006
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From: Sheboygan Wisconsin






That is possible, but generally when it'* fuel you will get more then one cylinder. I've seen 2 broken valve springs cause misfire under boost, but drove normal.
Thread Starter
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From: Neligh, Nebraska

Wouldn't you hear it though? My car sounds fine and the cylinder isn't completely dead only at certain rpms...we're running sea foam through it right now. I hope that it doesn't hurt it more, but we're trying it.
Joined: May 2006
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From: Sheboygan Wisconsin






Depends on the cover, the front is easy, the back is a pain. Both broken springs had no sign other then a miss. Even passed a compression test. We simply ran out of ideas and decided to look.
Make sure you check the coil where the spark plug wire plugs into it for corrosion. Takes just a few seconds. Corrosion on the number 5 coil caused a like problem for me.





