Had a freind bring by his 996TT that was having some odd boost and running issues. Erratic boost now and again, and then the CEL came on. CEL was due to the MAF sensor, which I replaced and took out for a test run. A lot of times erratic boost levels are due to bad MAF sensors. Unfortunately, we had two issues here. The other major cause of boost issues are spark plugs. On my test run, the CEL started …

Read more »