i got an 01 1.8t jetta i just put a blow off valve on it and now my check engine light keeps coming on i reset it twice so far. can anyone help me why does it keep coming on and how can i make it stop

 

did you upgrade the turbo or is the turbo stock? Also does the bypass valve have any leaks???? Do you see a drop in power, it could mean that the valve is stuck or inoperable. Plus how many miles does your car have? It could be something as simple as an o2 sensor amid the valve upgrade.

let me know more information i would like to help you fix the problem.