horrible surging - knocking

l/v attached. car started acting up this morning/afternoon after running great for some time. cannot keep steady rpms under throttle - knocking like hell.

datalog5.csv

Hey I found your new thread! That's scary that it's knocking just in your driveway!

 

Have you given any consideration to a boost leak test? It can be quick/easy if you'd like. Some have even had luck removing the big rubber intake hose from the airbox, and plugging the hose with a large plug (some say a spray paint can or cap is a close match), removing a hose from the intake like the brake booster or something and literally blowing into it with your mouth (no compressor needed!) If the leak is bad enough, it won't hold even that pressure, and you may hear it escaping somewhere.

 

Or... use a compressor at a very low setting. Even 5psi works for me. If it's much more than that, the evap solenoid starts honking like a goose, and if it's waay too much pressure you can blow seals etc. So basically keep the pressure reasonable.

unplugged the front o2 sensor and was able to at least hold a steady rpm without surging, so i'm gonna guess that's the problem. been running rich for a while now so i prob fouled it. gonna try to clean/de-gunk it but looks like my second $200 fooking sensor in 6 months.