1G Boost not holding

[Pat D]

I have a 90 TSI 5spd with a open K&N hacked mass MBC set to 15lbs,VDO boost gauge,Magna flow muffler 2.5 in 2.5 out and a hacked cat.
My problem is the car runs very strong but when I boost to 15lbs and my revs climb it doesn't stay at 15 it drops a few lbs to maybe 14 or 13 and hold there intil I shift. I have done alot of searches but most people have problem with boost creep and not my problem.
Any info will be helpful

Pat

 

[TheTSiGuy]

I remember when my boost wasnt holding, they all told me to check for boost leaks.

I didnt do a pressurized intake boost leak test, but i went around tightening all the hoses and clamps, and made sure everything was snug. Fired it up again, and i was holding full boost til redline. Just needed to be checked and tightened. You ought to try that.

 

[Pat D]

Thanks for the quick reply . I pressured the system and went over all the fitting,clamps and so on no leaks.

 

[dave99gst]

wastegate leaking? ( cracks around the flapper )

 

[Pat D]

Thanks Dave I did not think of looking there.