So, I had a 18g turbo, turbo XS TMIC, Sti pink injectors, walbro fuel pump installed on my 02 WRX. I also had a full turbo back installed about a year ago. After all was installed, it was being tuned, and the tuner said that it was knocking big time, especially at higher RPMs. So, we did a compression test and a leak down test, and everything looked fine. He mentioned that I should do an EVAP test to see if there is a leak somewhere. Anyone have any other ideas. Is there anything I can look for? I want to avoid shelling out even more money to find out what is NOT wrong with the car, ya know. I will do the EVAP test soon, but just wanted to get everyones thoughts first! Thanks!

 

what kind of knock?? maybe valve train noise? what kind of oil are you running?

 

could be an rod Bearing drain the oil and see if you have any copper or white meatal shavings could be the piston pin also. Evap test to be done on the purge valve which is behind the power steering pump. You disconnect the evap hose and you have to smoke the system for leaks. If he was an real tuner he would have offered that service in his shop. P&L does an optinal inspection which consists of leaks and smoking the system overall inspection for safe tunning.