Boost leak

[JJR]

I have a early 99 that leaks its boost. It only does it when the engine is warming up and at part throttle. Once it is at operating temp it is fine. I can hear a hissing noise when it does it and the boost gauge drops. I suspect something with the engine back pressure valve any thoughts.

[vitalidle]

Yeah sounds like your ebpv is sticking not letting you build boost. I had the same problem and unplugged the solenoid to the actuator before I gutted it.

[JJR]

Unplugging it seemed to fix it. Thanks