Q: Idles rough and when accelerating takes time to build up speed

asked by on December 21, 2017

After hurricane Irma , filled up with gas- truck miss firing I replaced coil, fuel pressure regulator, vacuum modulator for egr, map, newair filter, fuel filter, replaced screens on fuel injectors and rubber seals, replaced #2 fuel injector twice with injectors from eBay. Fuel injectors clicking OK, fuel pump pressure 44psi, have spark and fuel, pulled spark plugs. Allowed to spark on engine, all have spark on engine , added fuel cleaners to get rid of water. Used sea foam, gum out complete cleaner , and heet. Some improvement but not lasting. Truck still misfiring at idle, when step on accelerator takes a while to build up speed and kicks in at points of acceleration.
Autozone check light analysis, ASE tech solution is adjust values or settings . I don't agree with that .l did compression ck. On #2 cyl. It's 156psi codes from test po302 indicates #2 cyl.too many misfires within a predetermined period of time. Po302 cyl. 2 misfire detected Po300 multiple cyl. Misfire detected

My car has 250000 miles.
My car has an automatic transmission.

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Hi Paul. It certainly appears you’ve covered most of the bases in regards to tracking down a misfire. However, the problem with a flood or excessive water (like you’ve explained) is that quite often, electrical harnesses will become damaged and need to be replaced. If water found a way into the engine, it can take a considerable amount of time to clear up, and in most cases, it never improves. I’m not sure what to advise in this case, but you might want to have a professional mechanic come to your location to help you diagnose this issue, as a second set of eyes can be a huge help.

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