P1128 and P0172 Fault Codes on 2000 VW Jetta 2.0: Causes and Solutions
I recently experienced a check engine light on my 2000 VW Jetta 2.0, with the fault codes P1128 and P0170 appearing. The vehicle is equipped with an intake high-flow catalytic converter and a 2.5-inch exhaust system. I'm wondering whether these modifications could be contributing to the issue or if there's another underlying cause. If not related to the exhaust setup, what other potential problems should I investigate? Any insights would be greatly appreciated.
A poorly sealed MAF sensor in the snorkel could potentially trigger these codes, but a faulty oxygen (O2) sensor is also a likely contributor.