So it has come to my attention that since I got my car back from being stolen, if I shift just right (let the RPMs drop enough, i think), i'll get a nasty backfire. nothing horribly loud, just a very clear pop. Also it seems that when I'm coasting to a stop light in gear, the exhaust is very rough sounding. It's a shitty tsudo exhaust and the cat is dented and so is the piping in one spot.. could this be responsible, or am I looking at a much more serious issue? Oh and my DC headers appear to be scraped badly but it looks to be entirely cosmetic.

 

Annnnnyone?

 

probably clogged the cat when it was dented

 

its a hi-flow cat, and the dent is not to severe...

 

When was your car stolen? Where from? What kind of car? Im from LV, trying to keep my Civic on the D-L

 

Henderson, back on Sept 15th.

I have it back now, and the people who stole it were both caught in the act of stripping it. They both pled guilty to felonies. honda theft in vegas is absolutely out of control.

Anyone else have thoughts on the backfiring?? What can I do to help determine the source.. I want a new exhaust anyway, so I'm hoping it will be better after that.

 

could be anything from valves-exuast system-maybe even a o2 senor on th cat?

 

to my knowledge theres no o2 sensor on the cat? I do not have a CEL..

 

I've heard of just shitty *** exhaust designs causing backfires, is this at all possible?

 

Onnnneee more thing. The exhaust has a highpitched buzzing sound past about 3500-4000rpm. it sounds like a fleet of very determined bumble bees.

 

your cat has melted or broke apart almost 100% positive!!!


i bet they drove the **** out of this car heating up the cat and well there's your problem.

 

check spark plugs see if one is fouled, or wire is bad, letting HC's (raw fuel) in the exhaust system and at the cat since its so hot it combust there it was happeing on this one guys car at school

 

like people said, it sounds like either a broken up cat or did you check the o2 sensor on the header.
i have a bent cat and no o2 on my header rigth now and once in a while i get some backfiring.

 

My vote is for fouled plugs and/or clogged/broken cat.

 

Yeah I'm fairly convinced its either the cat, or the piping itself somehow. I've seen cars change over exhausts and just start backfiring, so its also a trait of shitty exhaust designs to cause a backfire. Either way I'm buying a new hiflow cat / greddy sp2 catback so if THAT doesn't solve it then I'll start looking at more serious things. But note: spark plugs look good and the wires seem to conduct properly (tried another set, same thing)

 

yup its the cat, once i changed my cat it cleared up that prob for me