93 civic DX not running right.
karnovking
06-22-2005, 06:01 PM
Most of the time my 93 civic DX runs fine, but on occasion it will have some hesitation or "sputtering" when I give it gas when pulling out. Today what bothered me was a heard a backfire when this occured.
about 3000 miles ago it passed the Pennsylvania emissions test well under the limits. And about 800 miles ago I changed the fuel filter.
The timing belt was also changed about 3000 miles ago also. But if it were a timing problem occuring from the belt change, i'd assume I would have noticed a difference right away.
Please Help!
about 3000 miles ago it passed the Pennsylvania emissions test well under the limits. And about 800 miles ago I changed the fuel filter.
The timing belt was also changed about 3000 miles ago also. But if it were a timing problem occuring from the belt change, i'd assume I would have noticed a difference right away.
Please Help!
curtis73
06-22-2005, 10:21 PM
Check TPS function, especially for the transition between idle and part throttle. If its not adjusted right it will wait too long to give more gas and the popping might be from a lean bog.
Try running some sort of upper cylinder cleaner. Most of the over-the-counter stuff doesn't work well, but GM has some stuff that works wonders. Ask a GM tech (since its not available to the general public) if you can get some of their upper cylinder cleaner stuff. You pull off a vacuum hose and stick it in the bottle. It drinks it in and cleans out a good bit of carbon junk. We used some on my friend's F150 and the black and grey stuff just came spewing out of the tailpipe. We found chunks of black flakes :) Not sure how much of the total it cleaned, but it made an impact anyway.
Pull all four spark plugs and check them for proper gap and for inconsistent buildup.
Does it only happen cold? hot? If it only happens hot, check the O2 sensor(s)
After a long highway trip, does the floor get excessively hot? Your catalytic converter may be plugged causing backfires or bogging.
I guess those are what I'd check first. Its so hard to tell, since almost anything can cause this kind of thing, but I would check fuel pressure which could be affected by the pump or the pressure regulator.
Good luck and let us know if there's anything else that is happening that might help us narrow it down.
Try running some sort of upper cylinder cleaner. Most of the over-the-counter stuff doesn't work well, but GM has some stuff that works wonders. Ask a GM tech (since its not available to the general public) if you can get some of their upper cylinder cleaner stuff. You pull off a vacuum hose and stick it in the bottle. It drinks it in and cleans out a good bit of carbon junk. We used some on my friend's F150 and the black and grey stuff just came spewing out of the tailpipe. We found chunks of black flakes :) Not sure how much of the total it cleaned, but it made an impact anyway.
Pull all four spark plugs and check them for proper gap and for inconsistent buildup.
Does it only happen cold? hot? If it only happens hot, check the O2 sensor(s)
After a long highway trip, does the floor get excessively hot? Your catalytic converter may be plugged causing backfires or bogging.
I guess those are what I'd check first. Its so hard to tell, since almost anything can cause this kind of thing, but I would check fuel pressure which could be affected by the pump or the pressure regulator.
Good luck and let us know if there's anything else that is happening that might help us narrow it down.
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