Help Please- Knock-Stutter etc.

[92ArcticTSi]

Hello guys, well my car is giving me some problems. 1st off is something that has been happeneing ever since i turned the boost down from 20 psi (when i bought it) to the 15psi its at now. Usually in 2nd or 3rd ger but not limited to those, under boost the car will stutter once or somethines twice for a second or 2, then pull to redline, best was i can describe the sound is like a stutterbox but while in motion and under boost. Second problem pretty much started yesterday. I will be cruising on the highway around 3k rpm in 5th under vac not boost and knock count will shoot up to 35+to 40+ from zero. If i downshift to 4th and get into boost i get no knock to worry about, maybe like 2-3 counts. It has been very chilly/rainy here and im not sure if that has anything to do with it. Thanks for reading this and any help in advance.

 

[TalonTsi85]

I'd check your plugs, NGK BPR7ES is the way to go. Depending on mods set the gap to .030 I think or .30 I cant remember off hand.