Hey, I got a 1999 a4 1.8t pretty much stock expect for a drilled airbox, 710N, and boost gauge. The car does have over 150k on it. Boost is around 5 psi.
With an APR chip it holds around 8 psi. Car does not have any check engine light. I have read other posts claiming that they are getting 8 psi stock and 15 psi chipped. I am definitely not even getting over 10 psi. I have checked to see if I was in limp mode but am not. Could my turbo getting old...Any suggestions?

 

check for leaks.. do a boost leak test

 

its most likely really big boost leak i would check that back of the boost gauge and all line's on the car at that age of the car the rubber is going to start going bad

 

going to test for leaks tomorrow...

 

Could be a leak but it does sound like your car is in limp, 5psi is limp for stock tune and around 10psi for a chip tune. Normally you should be seeing about 15+psi on a chip tune.

 

lots of leaks!!! did a smoke test and smoke was pissing out one of the check valves completely rotted on underside near airbox...plugged that hole and then also smoke coming out of oil cap and dipstick. will try to replace next week

 

found the problem...needs new wastegate actuator