If you want some more power and retain your upgrade DP, get a stage 2 tune. O2 spacers aren't guaranteed to work and the CEL will come on, eventually. If you're worried about wear and tear on your engine, buy an electric car...like a Prius.
If you want some more power and retain your upgrade DP, get a stage 2 tune. O2 spacers aren't guaranteed to work and the CEL will come on, eventually. If you're worried about wear and tear on your engine, buy an electric car...like a Prius.
The car will adjust to compensate if there is any risk of it running lean by adjusting the timing and a downpipe alone will not cause this to happen. A downpipe alone can cause this issue in a WRX or an exhaust can cause this with a motorcycle but not a GTI. I'm going to take a guess and say that your haven't thrown any codes related to a lean condition and you won't.
If you are that worried about it running lean pull your plugs and learn how to read them through Google.
