sounds like injectors are sqeeling?
 

1994 supra twin (replaced by one large turbo) started a high piched sqeele sounds like it is coming from the feul rail and injectors? please help?:help:

Hopefully some more folks will pitch in.... the first couple things which come to mind for me are a whistling caused by a leaking O-ring on the head side of an injector or a squeal from a failing fuel pressure regulator. I've never had to deal with this though. I'd get a stethoscope and try to pinpoint it.

Assuming this noise started after replacing a turbo, check the turbo is bolted down correctly; I had a high pitch screaming noise from my turbo (especially when cold) turn out to be the 4 bolts holding the turbo to the exhaust manifold where loose.

Correction; this was under boost condition, obviously your noise may or not be.