[Andrewah05]

BMW emissions warranty replaced my two catalytic converters and resonators, was wondering if ill see any performance gains or better gas mileage or any other changes?

Regards,

Drew

[AviatorBimmer]

Why would you see a performance gain when replacing a stock part with another stock part?

[Andrewah05]

Just curious, because if my cats were malfunctioning, any malfunctioning engine part in that case, wouldn't it hinder performance, I don't mean every part but certain ones like this that involve air flow.

[Kolyan2k]

why did they replace cats ?

[AviatorBimmer]

Oh ok, well if performance was being hindered due to a bad part, then replacing it with the exact stock part would return the performance to normal levels. Not increase or boost performance.

[Andrewah05]

Originally Posted by Kolyan2k

why did they replace cats ?

Had a lean code for bank 2 then 2 more codes came up both stating faulty cats

[Andrewah05]

Originally Posted by AviatorBimmer

Oh ok, well if performance was being hindered due to a bad part, then replacing it with the exact stock part would return the performance to normal levels. Not increase or boost performance.

Lol you are correct good sir, my phrasing was inappropriate I apologize..

[AviatorBimmer]

Originally Posted by Andrewah05

Lol you are correct good sir, my phrasing was inappropriate I apologize..

Lol it's all good, brother!

[46m3csl]

Yeah 20whp gain, jk. Really haha nice post. Least you got new stuff for free

[ef11]

Originally Posted by Andrewah05

BMW emissions warranty replaced my two catalytic converters and resonators, was wondering if ill see any performance gains or better gas mileage or any other changes?

Regards,

Drew

I've had the same thing done by the dealership for free. I told them my honeycomb was rattling and after a week of diasgnosing it they finally called to tell me I was right ha.

Car seems to drive the exact same, just quiter at 5mph through a parking garage

[Andrewah05]

Originally Posted by ericfox11

I've had the same thing done by the dealership for free. I told them my honeycomb was rattling and after a week of diasgnosing it they finally called to tell me I was right ha.

Car seems to drive the exact same, just quiter at 5mph through a parking garage

i miss the loudness I had from mine, do you have the golf tee mod done?

[ef11]

Originally Posted by Andrewah05

i miss the loudness I had from mine, do you have the golf tee mod done?

Well I pulled the plug in the trunk, so technically not the golf tee mod but same effect.

And by being quiter at 5MPH in the parking garage, I meant I can't hear the honeycomb in the Cat rattling like a POS car ha.

[John 070]

With those parts being so expensive, I would not want them replaced...it always seems that what came with the car is better than what it gets replaced with, even OEM. On my Nissan the original exhaust lasted 12 years. The replacement 18 mos. Nice when the s*** breaks out of the original warranty. Our exhaust costs $6,300 retail, nothing is cheap.