Hi Guys

I installed a Borla catback exhaust system about two day ago.. Every thing lined up , also I have made sure I rechecked, all the clamps are tight.

Been driving it since and have covered about 300km (±180 mile) so far, and I am a bit worried.

The idling rpm is now 700rpm (I think it used to be 500rpm-if memory serves rite)

I have notice back firing at times-not all the time -some times quite loud.

I have also noticed, there is rpm hesitation from 4k to 6k rpm under WOT,(4,5,6th gears) its like some thing is holding it back and then suddenly power is back and goes normally- this does not happen all the time.

Under normal city driving no problems at all.

There are no engine lights/warnings etc.

I use 95 oct unleaded- always.

The only other mod car has is JoeZ intake.

I have no way to check for error codes ( are there error codes that don't actually show up on the instrument cluster? Until one checks for them?)

Anyone experiance any of these issuess? Or is it jus me

Will appreciate your thoughts.

 

You have nothing to worry about. You ECM is just re learning the more exhaust flow you have. The back firing is normal having remove the secondary cats. I actually like it. Im not sure about the idling. Its maybe because of better exhaust flow. Most car idles at 700rmp.

 

Backfiring? Or do you mean a "burbling" type sound? I had a 6L v8 with long tube headers no cats and full exhaust..it never backfired. I would double check your O2 sensors are connected and not damaged...however i would assume that you would have seen a check engine light if something was wrong..hmmmmm

 

My JoeZ exhaust backfires pretty loud. It doesn't happen all the time and only happens when I let off the gas to engine brake. It scares the crap out of my wife when it happens. I thought it was normal lol.

 

I don't think you have anything to worry about.

I also have the Joe Z exhaust and it back fires quite loudly all the time. I have race cats and still back fires. I kinda like it.

 

I wish my Joe Z/PPE would back fire more....

 

I figured out how to make it backfire... Just bounce off the rev limiter and you'll be backfiring like an F40.

 

Sounds normal to me

 

Thanks guys

I feel much better, though still curious about the rev hesitation, the dips and surge in power under WOT....

 

I think your just being a bit of a worry wort.

 

Stay in sport mode so you dont have to worry about hesitation.

 

Sikky/Joe Z.... backfires all the time.

 

You'll be fine. Just keep any eye on it.....