[PETED678]

Wonder if anyone has any ideas?

I recently changed my turbo to a Garret Turbo to replace my failing turbo, but ever since I installed > Primed the turbo with oil > Started the engine I keep hearing a hissing sound from the turbo when accelerating it was bad Saturday but you can no longer hear with the windows up. With windows down you can hear it along with the woosh sound.

I have double checked the two ports from the manifold to the turbo and don’t feel any exhaust blows or see any soot. Thought it maybe was a bad exhaust pressure sensor? Only been driving for 30 miles max.

Also is there a ‘bedding in’ period in which the turbo needs to complete? As a precaution I have been driving carefully anyway.

[Shirazkhan]

Check the boost pipes or the seal on the boost pipes.Any dtc?

[PETED678]

Only had one for a P0299’Turbo underboost’ but only occurs if I put the car on sport mode and leave the gear in 4th when accelerating hard

[E36M3]

If we assume the new turbo is still good there are only so many causes of turbo underboost that you need to solve to see if it is contributing to the noise. Boost leak on the intake side, exhaust leak before the turbine, wastegate issues (improper adjustment, not dealing, actuator bad) or blow off valve leaking excluding actual engines issues like cam timing or valve sealing issues. I would start with a boost leak test and then check the wastegate system.