Idling problem after downpipe gutted?

[kevinye77137]

Does anyone have an idling problem after gutting your downpipes? It doesn't happen all the time but the rpm drops around 100 rpm and the car shakes abit then goes back to normal. Went to a mechanic to check if there was an exhaust leak and there wasn't.

[getslideways]

The O2 sensors can get damaged during removal or install, especially if they are old. Also check your intake connections for anything you moved to gain access for removal of the pipes. unmetered air getting in would definitely cause idle issues.

Tossing any codes? The CEL does not need to be on for codes to be present.

[kevinye77137]

The O2 sensors can get damaged during removal or install, especially if they are old. Also check your intake connections for anything you moved to gain access for removal of the pipes. unmetered air getting in would definitely cause idle issues.

Tossing any codes? The CEL does not need to be on for codes to be present.

Thanks I will check on my 02 sensors. Yes I had some codes on thrust hold on both banks. I cleared it and it didn't come back.I cut out my bank 2 sensor 2 02 wires and remember one of the wires i tried to reconnect back only had half the copper stripes left on it. I didn't bother cutting it again because I thought it was fine, not knowing about electrical things. Could that cause the problem? I also replaced bank 1 sensor 2 02 sensor and still had idle problem

[jakeoboy67]

Thanks I will check on my 02 sensors. Yes I had some codes on thrust hold on both banks. I cleared it and it didn't come back.I cut out my bank 2 sensor 2 02 wires and remember one of the wires i tried to reconnect back only had half the copper stripes left on it. I didn't bother cutting it again because I thought it was fine, not knowing about electrical things. Could that cause the problem? I also replaced bank 1 sensor 2 02 sensor and still had idle problem

there's your problem

[MyB7S4BlowedUp]

Did you disconnect the battery?

Sensor two behind the cats monitors Cat efficiency and not Air/Fuel.

Try cleaning your throttle body and resetting the adaptation with a VAG com or if you can't find that the dealer shouldn't charge to much to run the adaptation.

[kevinye77137]

Did you disconnect the battery?

Sensor two behind the cats monitors Cat efficiency and not Air/Fuel.

Try cleaning your throttle body and resetting the adaptation with a VAG com or if you can't find that the dealer shouldn't charge to much to run the adaptation.

so the 02 sensor 2 on the main cats does not manage air fuel ratio? I disconnected the battery when I did my pre cats. I will try resetting the throttle body tomorrow

[kevinye77137]

Problem solved... I added 02 spacers on the pre-cats 02 sensor which Im not supose to... Dam I feel dumb...

[getslideways]

/\ LOL

At least you got it sorted. We all have those moments from time to time. Hopefully by you not being shy regarding posting the solution, you will have prevented someone else from doing the same later.