what can cause this?

[Chatmanboy]

car doesnt boost right!

Go WOT and the boost gauge hit about 15#s no more and the car doesnt respond just rpm creep up and the engine revs. (NO KNOCK)

Yet at about 7-10# of boost the car go but once i go wide open throttle it just falls on its face. I added and subtracted fuel but same result

Thanks for the help in advance

 

[Gnology]

Does it surge? Fuel volume delivery? What boost does it normally have?

 

[Chatmanboy]

yes that exactly what it does, and i have it set at 43 psi line off. just have it at 15 since im not getting the response im expecting

 

[Gnology]

Usually surging indicates a fuel delivery issue. Do you have a fp gauge you can see under boost? If so, look for fp to drop under WOT. I've seen a fuel filter cause this in the past.

 

[Chatmanboy]

ok ill give that a try thanks for the advice