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?

 

[boostedinaz]

What kind of car what mods?

I am guessing he is getting boost creep, but with not knowing much it is hard to say.

 

[danyz250f]

Woops. 95 gst 14b huge xs power fmic, mbc set at 14lbs, cone filter, boost guage,fuel pump rewire, 1g bov. Every thing else is stock.

He said his boost stays the same as it used too which was 14lbs. But I dont know I havent ridden with him yet, just drove next to him.

 

[kenamond]

Maybe you damaged the O2 sensor, and it's running rich and backfiring?

 

[danyz250f]

Would taking the sensor out and wrapping it in foil and plugging the hole help.

 

[crunchymilk]

the only 02 sensor you would have messed with is the rear 02 sensor, which doesn't affect a/f at all. Perhaps you have boost creep because of this exhaust, your friend might not notice it because he's watching the road, but he is probably overboosting causing fuel cut.

 

[danyz250f]

Nope he has no boost creep, also there is a burning smell and he can smell it the most by the exhausty gaskets. The tub of the car does not feel exessively warm.

 

[kawboy]

The smell is most likely just the new exhaust piping/gaskets "burning" in.

As for backfiring, what octane gas is he running?

It's possible that the engine is knocking excessively and timing is being pulled. May even be phantom knock, which would cause the loss of power, then letting off and getting back on the throttle to fix it.

 

[chris4g63t]

Check ignition timing. When was the last time the car got new plugs and wires?

 

[95TalonOwner]

Did you reattach the ground wire that goes to the exhaust pipe? I'm not sure if 2g turbos have it but I know my 1g turbo did.

 

[IslanderTsi]

If he went with a cat delete setup then its gonna smell. Nothing you can really do about it. So all the routine checks like vacume lines, boost leak, check the plugs, fuel filter etc. SOund like he is running rich.

 

[danyz250f]

Plugs and wires are new, premium gas, but I dont know about the ground wire. He has a 14b turbo at 14 lbs with the fuel pump rewire. Could this be to much boost. He has a new fuel filter too. All the maintance is done he got a new timing belt job done about 1000 miles ago. I told him his ecu might have to ajust to It and he should try turning down the boost.

 

[crunchymilk]

I'm perplexed here.

Try resetting the ecu, unplug the battery for a few minutes, see if it can adjust.

 

[danyz250f]

His profile name is 95'gst and he is from rexburg Idaho if you want to see his profile.

We will try reseting the ecu.

 

[Ajax]

Just for curiousity what does the ground wire do? Bc mine is not attached-custom pipe and it backfires

 

[95TalonOwner]

I'm pretty sure it helps ground the o2 sensor.

 

[danyz250f]

Thanks we will try that.

 

[4BangR-x]

I realize you said you have new plugs and wires, but dont rule that out. What kind of plugs and wires are they?

 

[chris4g63t]

Always use ngk bpr7es on a modded dsm

 

[IslanderTsi]

Always use ngk bpr7es on a modded dsm

Not true. You should only really step up to 7's once you are making somehweres around 100hp over stock. BPR6es are best for most mild apllications

 

[Eclipse98Spyder]

Always use ngk bpr7es on a modded dsm

Well he beat me to it but I was told that is not true unless like he said your running 100p+ over stock

 

[Byrd]

Might sound stupid, but maybe all you have to do is lean it out?
Does it have a cat?
Any logging/tuning device?

 

[chris4g63t]

Not true. You should only really step up to 7's once you are making somehweres around 100hp over stock. BPR6es are best for most mild apllications

My car ran perfect with the bpr7es's when my car had only an intake pipe and full exhaust. Where have you heard this and have you had a bad experience with the bpr6es's?

 

[95TalonOwner]

7's run colder than 6's therefore they would work best with higher heat applications for example a more heavily modded car with higher boost which would create a higher heat within the engine.

7's are still good for the car, but 6's are best for only mild modded dsm's.

 

[PieEyedPiper]

Do we have an update on this? Did grounding your setup work?