Hi everyone. I have a backfiring problem with my ride. I have a 90 integra with a b16a and whenever I shift from 1st to 2nd gear there is a loud pop. it happens when i shift from 2nd to 3rd also but it is not as loud. Under circumstances where I can drive faster and shift higher it seems like it doesn't happen as often (like nobody in front of me at a red light) but if I'm driving in traffic or under normal driving conditions and shifting lower it always seems to occur. My mechanic says it can either be I need a new muffler or my car needs tuning. I don't know which one but I don't wanna waste money. Can one of you guys please tell me why this is happening? I would appreciate this a lot. This has been happening for years. Thanks

 

You have an aftermarket exhaust? The larger 2.5" and 3" exhausts do that. My 2000 Teg does it all the time, I don't think it's really a bad thing. Hard to keep it quiet sometimes, tho!

 

Yes I have aftermarket 2 1/4" piping and a Magnaflow muffler. My car runs pretty good but once the car warms up shifting into 2nd it's constant, as well as 3rd...and quite loud. I would just like to shift smoothly without everyone staring at my car once I shift. And its like I don't hear any other car backfiring like mine. Is there anything I could do to get rid of the backfiring completely?

 

Not sure, you could try a different muffler setup? My bud has a Mazda MX-3 and he has put a 2 1/4 Magnaflow setup on it probably very similar to yours and his gets that backfire and popping sound when he shifts too. It's just the nature of the bigger exhaust systems. I've read about people putting resonators on them and such, but it seems like a resonator is like a amplification chamber, maybe I'm mis-understanding it.

See about a muffler, but that will cut into your performance and point of having larger piping.

Good luck, mang!

 

Are you running a Catalytic Converter, and resonator?
Is your MIL, otherwise known as CEL illuminated?
Have you checked your ignition timing?
What about your Oxygen Sensors, are they in there stock locations and functioning properly?

 

I guess its just the Magnaflow mufflers then. I don't want to lose performance either so I'll look into some other exhaust setups and hopefully that will work. Actually I just remembered the last time I went to another one of my mechanics he said that it seems like my catalytic converter was hollowed out....aparently done for performance. I don't remember letting anyone do that but whatever. Maybe that has something to do with it.

Thanks a lot for all your advice man. It was very helpful.

Peace

 

One other thing I forgot, sometimes a backfire is a sign of blow-by. Might be as simple as your PCV valve.

If your CAT is hollowed or bad, thats more than likely the culprit. Performance benefits are < 1 HP, on a stock car. Put a functioning CAT on, check O2 sensors, and breathe clean. Good luck!

 

Good call 2001, I forgot I have a gutted cat.h:

 

I believe my catalytic converter is hollowed out and I don't think I have a resonator. Should I have a specific type of Catalytic Converter? What's the deal with the resonator? Should I be running one? Sorry but I'm not too familiar with all the technical terms and I don't know what a MIL or CEL is. (probably the only guy on here who doesn't) I haven't checked my ignition timing but now I will if you think that might be a cause. Regarding my O2 sensors I don't think they are in the stock locations but I have had serious idling problems back in the days with engine lights coming on and all of that. The O2 sensors were to blame but those days are over so I believe they are running properly.

Thanks for your advice. It has been helpful.

 

CEL= Check Engine Light. Not sure on cat choices, I know edelbrock makes em. Or you could try to find a stocker.

It's ok to be knew, I'm no expert either, Im learning as we go too. Everyone has to start somewhere!