compression test

[TT_Stealth]

I did a compression test today on the TSI, across all 4 cylinders it read about 125, The cars turbo spools but dont feel any boost. I have checked the wastegate already, thats operational, no boost/vacuum leaks anywhere, no evidence of water (blown head gasket) in the oil, and no steam out of the exhaust. I datalogged it and the Timing advance when I wasnt in boost read as high as 38 sometimes, then when I hit boost read around 28 or so, and jumps around. Nothing is consistent in the readings. O2 voltage is about the only thing that is consistent. Any suggestions on what might be going on?

 

[TT_Stealth]

Another thing to add as well, I see a consistent reading in my boost gauge, it peaks at 20 lbs, I can feel the boost up until about 10 psi then the power seems to "fade" off as though the wastegate has just gone wide open. No bent valves obviously, sooo, I am stumped by this one??

 

[Anubis_4_99]

isnt that compression a bit low? i did mine on saturday and got 150 across the board

 

[oldman]

He's right, 131 is the service limit. Was the compression test perform with the car fully warmed up? Full throttle? Perform the test again dry and wet to see if the rings are bad. If wet test yields nothing, you will need to do a leak down test to see if it's valves or HG. Good luck.