I've almost given up on keeping Test pipe. The infamous CEL just won't go away. How much HP do you really gain. Does keeping Test pipe make sense? Is it more trouble than it's worth? My mechanic told me the engine is working harder due to no back pressure and that it will run too lean which will hurt my engine in the long run. The car runs fine but that CEL just bugs the hell out of me. Does anybody have advise on this topic? Thanx!!

 

Did you purchase a test pipe with the CEL fix bung welded to it? Mine was a CEL fix model but still caused a CEL. I contacted Invidia and they sent me a defouler for free which has worked flawlessly for many years.
A test pipe alone isn't enough to harm the motor. Plenty of people are running test pipes with other bolt on modifications (intake, header, exhaust) and have no issues. It's really up to you if it's worth it. For me, putting the cat back on for smog was super quick and easy so a test pipe was no concern.

 

if youre an 06+ buy a Flashpro. if youre 00-05 just try a CEL fix...my '05 was fine with one and now the '07 has secondary disable.

 

So far my '06 is doing fine with just the DIY CEL fix (knocks on wood).

 

Thanks for the responses. I will keep it installed for a little bit longer. I'll try getting that CEL fix very soon.