Ive had a CEL on since I installed my used Apex'i dual World Sport exhaust. I failed my smog test due to it have a knock sensor. Does anybody know why it might do this? It makes a quiet "putt putt" sound while idling. Either way, my new exhaust will be ordered Monday or Tuesday.

Ryan

 

- is that exhaust cat-back only??
- if it is, it SHOULD NOT effect anything (problem you're having) at all..

 

Im not sure what you mean? Is it possibly caused by the person before me having a test pipe? When I installed it, it had a lot of carbon build-up as well?! Thanks for your time!

Ryan

 

- are YOU using the test pipe?

 

I am not. I dont have one installed and never have before.

 

- you should be fine.. I don't see how the exhaust is at fault...

 

Reset you CEL and see if it comes back on. A cat back exhaust should have no effect on the engine unless it's totally clogged up with something not allowing exhaust flow.

 

- like a bannana

 

Any clue what else it could be? The CEL has been cleared many times. It really started RIGHT after I got the exhaust installed.

 

- check the code at autozone