so yesterday the car was running great, i went to go get gas at exxon filled up with 93. i drove down the highway and the car was fine boosting normal and all. I went to eat with a bunch of friends and the car sat for about an hour. after i got in started it up and it seemed to be fine. on the drive home i noticed i was only boosting to about 8-9psi when i usually boost 18-20psi and it felt like there was maybe a boost leak. got home checked it out with a presure test but found no leaks and my boost guage reads 20hg. i noticed when i did the pressure test there was air rushing out from my oil cap on top of the block is this normal when you pressure test. i mean i had a friend hold it down so no air would come out and not one hose was leaking so idk how the hell i lost almost 10psi with no leak. could it be bad gas. oh and there are no codes and my turbo is not making a drill noise...

 

codes would be my first choice then check the turbo waste gate solenoid or linkage unhooked ( turbo is not my area ) but a blocked system would answer the question ) back pressure through the oil cap for instance but just a guess others will know better

 

this has got me stumped, sometimes the boost will go up to say 10-12psi and them when i take my foot off the gas and go again it will bosst to only 5-6psi

 

sounds like a vacuum leak or air leak, check all the pipe clamps or piping for breaks/cracks

 

most notorious problem here is a crack in the exhaust down pipe after the turbo on the flange

 

is there a way i can check to see if my wastegate is bad?

 

so the wastegate on my turbo finally went, i can hear it flapping around and now i make 0psi. WOOO HOOOO its BT time