Happens to me all the time although its not an fsport exhaust. Also happened when i had my hi power

 

are you sure its the deleted cat??? i thought the invidia deletes the second resonator. the cats are on the exhaust manifold.

 

There's primary and secondary cats on the car.

it's why midpipes aren't street legal.

 

yeah, from my understanding the cats are on the exhaust manifold and resonators are located on the mid pipes. stock has two and indivia has 1 resonator.

 

I get small backfiring on deceleration with PPE headers, stock mid and some straight through resonators at the back. I think, like another poster said, the car has a tendency to back fire from the factory and that the stock mufflers make it quiet enough so that you cant tell.

 

I get a small pop with just f sport exhaust. Don't remember it being louder when I had invidia mid

 

The primary cats are part of the manifold.

The secondary cats are part of what the midpipe replaces.

The 1 resonator sits behind the secondary cats.

diagram here-
http://is.sewellparts.com/images/oem...000/176073.jpg


Diagram of the manifolds with the primaries here:
http://is.sewellparts.com/images/oem...000/176453.jpg

 

I finally figured out how to stop the backfiring. Just in case there is a police behind me I now know what to do.

When you are coming to a stop, just drop your car to neutral.

 

I did notice my car backfire today. Was slowing down to go up the driveway at work and bairly gave it any gas to accelerate up it and i heard a very faint pop'ing sound.

 

I got it after installing the axle back, and still had it after my resonator delete. Plan on installing the mid pipes next week (Invidia), and will update this thread with and change. My understanding is that it is more a pop because the exhaust takes in colder air, than it is a true backfire. Not sure if that's accurate though. Just what I have been told by others with aftermarket exhaust.

 

YA when you change your midpipe you will notice a much louder, and more often backfire