i have a 03 s2k invidia test pipe hyper medallion touring exhaust aem intake... and a few other lil engine goodies... on cold starts from 1st to 2nd this sucker back fires like a f1 car... wondering why? when warmed hardly ever does that? wondering why it back fires on cold starts or not all the time ect. thanks

 

The car give more fuel when cold to help warm it up, my civic use to do it and my S does too.

 

During cold start, cars run in closed loop, which is richer (more fuel) than normal. Some unburnt fuel can ignite in the exhaust once it meets some oxygen.

Now, a gun shot type backfire is cause for concern, but gurgling or popping is normal with no catalytic converter.

 

Normal ? I've got 105,000 miles on mine and it's never backfired. I do get the gurgling / popping, but never a true backfire.

 

Backfire is usually due to a leak in the exhaust system. I had a hairline crack in my header on my s2k. You couldn't even hear a leak. but is was enough to cause small backfires. Air gets in the crack on decel and re-ignites the exhaust.

 

You dont have an anti lag system do you ?? just joking...if it does backfire constantly keep an eye on the cat...backfires tend to destroy cats

 

i have the same set up, but no backfire, just a deep gurggling from shifting from 1st to 2nd...
And its been like that pretty much ever since i put those bolts-ons on..

 

the only backfires ive ever had are shifting around 8kish. i had a pop last night. very rarely do i have that. lol. i just have gargling going from 1st to 2nd when its cold...sounds good.

 

My brother has a 06 m coupe it's always back firing even though it's tuned. Last night I had a tru back fire from 1st 2nd similar to a srt4. Took it to 4k put it i'n 2nd n boom then the piping gurgling... Just made me wonder that's all.... Hasn't dome it again normal gurgling when cold. If I get tuned on aem will the gurgling be constant similar to obd1 vehicles.... Rx7s 240s ect.... Lower emission vehicles?

 

What he said.

I think you need to give us more info on the "backfire" you're hearing.