Backfire Problem NEED HELP BAD!!!!!!

[Blacke17]

I have read other posts on this problem but none of them seem to fit my exact problem. I own a 1999 Mitsubishi Eclipse GS-T and my problem is that my car seems to backfire in 3rd and 4th gear at around 4500RPM's. ALSO my exhaust seems to leave black residue on my back bumper so im guessing it is running rich as well. I believe i can also smell gas in my oil which makes no sense at all. i don't understand what is causing this problem and where i live, nobody really knows much about DSM's or turbocharged vehicles...

some solutions i have tried were replacing the spark plugs, spark plug wires, and coolant temp sensors. i dont believe that my mas is bad, but i really could be wrong. My K&N air filter was crushed by past damage from the previous owner so i bought a cheap spectre filter from advanced auto to replace it. im running normal boost with a 1G BOV.

Once this problem is fixed i plan on racing my brothers 1999 Mitsubishi Galant v6 cause he thinks he can keep up


It would be really helpful to get the problem solved BEFORE the MOD meet October 16th. If i missed any information please let me know. Thank You!!

 

[crasher28]

Is it smoking at all?

 

[Blacke17]

it doesnt smoke at all but my brother had told me that when he followed me one day as soon as it backfired i had a puff of black smoke.

 

[Indian]

This happened to me when my coil pack went bad. Also it seemed to get worse as time went on. Just a suggestion.

 

[Vladimir]

Yeah, I had to replace my coilpack cause of the same problem

 

[chico904]

What did you gap your plugs to? Always safe to recheck them.

 

[Blacke17]

well i dont know the numbers of the gap off the top of my head but i gapped them at what the manual had told me, i think its 28-30 or something like that.

i really hope its the coil pack ill be amazed cause this problem has been making me doubt the eclipse (no offense to anyone of you guys) i just was getting pretty upset with it and i did not want to have to go through every part to see what was going on. thank you

 

[crasher28]

You may also want to check ignition timing. Although it seems more likely to be the coil pack.

 

[steve]

When was the last time you pressure tested the intake (boost leak test)?
When it backfires does it really start popping out the intake or is it misfiring and feeling like it's loosing power?

 

[Blacke17]

hey guys thank you so much for helping me, it was the coil pack.. though i only bought one and didn't realize there were two total, so i tried it on the right side and it didnt fix it so i got really worried thinking that it wasn't going to fix the problem, so i put it on the left side and took it for a drive.. it had backfired once and got me really mad so i downshifted to second gear and then shifted right to third and brought it up to 6000 and guess what? NO BACKFIRE!!... so i tested it on many runs and has not backfired. though i probably should get another coil pack and replace the other used one so the problem doesn't occur anymore.

I'm really glad that you guys could help me right before Mitsubishi Owner's Day. It's also the day of my birthday . I really didn't think anyone was going to message me back in time so thanks a lot for your help i really appreciate it.