If I was to straight pipe my 01 1.8t from the cat back would I run into a CEL? Also would I notice any performance gains?

 

are you tuned?

i am running a test pipe all the way back to my muffler..... if you skipped the muffler you would have even more drone than i do....

to answer you question, you would probably have a cel for your o2 readiness at least unless you have it shimmed so far back or written out of your ecu....

and to answer the other part, yes your turbo would breathe better, but if you use stock exhaust except for 2 or 3 straight pieces it would be worthless cause it is semi-restictive... you would want custom pipe.... but with a stock turbo it might be 5-10 crank hp which if you are quattro will only equate to a little bit of tq, no true hp gains



get a tune and a tp and start going from there




also read the stickies on what make more power

 

If anything delete the cat and use a test pipe there. The cat is the most restrictive part of the exhaust. The resonator and muffler don't really hold you back at all, but the turbo does need some back pressure.