new 3 in exhaust and now it backfires

[danyz250f]

My friend bought new tsudo 3in cat back exhaust and we put it on and now it backfires. We left the o2 sensor alone and screwed it in the new exhaust because it has a bung for it. All we did was unbolt stock stuff then bolt in new stuff. It looks great by the way and sounds sweet too.

But anyway when he accelerates it will some times backfire and he loses all power. Till he lets off and accelerates again.

Any suggestions on what is going on?

 

[boostdog]

ya what happened i want to know too. the only time mine ever back fired was when i was running rich on race gas...i bet the ground wire will fix it or he screwed up the sensor while putting it back together.

 

[95'gst]

Hey guys thanks for all the responses. Its my car that my friend started the thread for. My friend dan gets to play on the computer while he is at work so he usually gets my questions posted before i can.

However the problem is still not fixed. My ground was on the whole time ### its hooked on by the cat and i havent done anything with that. I tried resetting the ecu, I turned down the boost to 11psi. My logger just came in the mail yesterday and sure enough i have timing getting pulled from knock. So i Think i need to follow the cardinal rule and do a boost leak test. But are there any other ideas

 

[Byrd]

Yea do a leak test and then tune from there and you should be good. I'm getting crazy knock from leaks right now as well (they never end)

 

[danyz250f]

Boost leaks. Blake changed a coupler on the TB pipe the other day and It was leaking really bad. This was just before the exhaust install. To an earlier question no he has no tuning device just a new ob2 logger that we dont really know how to review logs with.

Remember Kids every time you mess with IC pipes do a leak test.

I have not rode in it yet but he says his car is fast again.

Also he has the xs power fmic and that think is huge, He has a 14b so I think he is getting bad pipe lag. Would a evo 3 16g be a good turbo to help him spool faster. (my turbo that is on my car so I can get a bigger one) Or would it be worth it to port the 14b.

So blake I think some of these guys deserve some rep points for there insightfull suggestions.

 

[Byrd]

Glad all is well in your neck of the woods. But I JUST GOT THE SAME FREAKIN PROBLEM! i JUST switched to a full 3inch and i just started getting backfiring when at idle and deceleration.

Where would this ground wire be? I didn't see anything like that on my old exhaust

I plan on leak testing and changing plugs. I'll keep you posted