BIG PROBLEM misfires like a SOB!
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Joined: Mar 2003
Posts: 8,319
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From: North Carolina
BIG PROBLEM misfires like a SOB! ok ill just go from the beginning
about a month ago my frined came back from the navy and his car felt like it was missing at about 3500 rpm. we did fuel filter, plugs and wires. car felt good after that and then felt a lot worse. i looked at the parameters on the predator and noticed fuel trims were maxed out. put on my old slp maf and the car ran perfect and strong and smooth. numbers were normal. next day the car went to **** again. we tried some new plugs and wires that i had lying around and that didnt work. we tried to swap in his old rear o2s, that didnt work. looked inside the intake manifold and no oil.
ok well we left it at that and the car was jerking really bad. well he came back now, 3 weeks later and the car doesnt jerk but still throws the p0300 misfire code. now its puffing blue smoke out of the tail pipes really bad. i looked at WOT o2's and 3 of 4 runs it read 0-400mv and one run they read about 860-940mv. there was 7* of KR!!!
what i think: maybe a fuel pump not supplying enough fuel to the motor? stoped up injectors taht arent working right? but then why would it go from bad to good to bad then perfect right back to bad again? this is where im lost. about all i am pretty sure about is the car is running really lean, causing detonation and fouling of plugs and wearingon the rings causign the smoke.
also, pulled the plugs and they were a brownish kind of color. any body have any kind of idea what is goin on here? i have about lost it tryin to figure this out, i just cant!
about a month ago my frined came back from the navy and his car felt like it was missing at about 3500 rpm. we did fuel filter, plugs and wires. car felt good after that and then felt a lot worse. i looked at the parameters on the predator and noticed fuel trims were maxed out. put on my old slp maf and the car ran perfect and strong and smooth. numbers were normal. next day the car went to **** again. we tried some new plugs and wires that i had lying around and that didnt work. we tried to swap in his old rear o2s, that didnt work. looked inside the intake manifold and no oil.
ok well we left it at that and the car was jerking really bad. well he came back now, 3 weeks later and the car doesnt jerk but still throws the p0300 misfire code. now its puffing blue smoke out of the tail pipes really bad. i looked at WOT o2's and 3 of 4 runs it read 0-400mv and one run they read about 860-940mv. there was 7* of KR!!!
what i think: maybe a fuel pump not supplying enough fuel to the motor? stoped up injectors taht arent working right? but then why would it go from bad to good to bad then perfect right back to bad again? this is where im lost. about all i am pretty sure about is the car is running really lean, causing detonation and fouling of plugs and wearingon the rings causign the smoke.
also, pulled the plugs and they were a brownish kind of color. any body have any kind of idea what is goin on here? i have about lost it tryin to figure this out, i just cant!
Try the Front O2 Sensors, my car did the same thing for a month before we figured it out and spent alot of money on unneeded parts. 
Try the Front O2 Sensors!! Hope this helps!!!!! This is what fixed my car!!!! Now she is back to normal 
Try the Front O2 Sensors!! Hope this helps!!!!! This is what fixed my car!!!! Now she is back to normal Trending Topics
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