87 3.2 Carrera engine in a 914 with all the FI, starting, idling, easy driving, no unusual sound. Then if I really get on it for a few seconds I get the loud whining sound that modulates up and down. eeeeeee-awawawaw-eeeeeee-aawaawawaw. when I come off the gas it slowly quiets down and goes away. Sounds like it is coming from the right side of the engine bay. There is no noticable performance loss during acceleration, just the noise. It doesn't happen if I just rev. the engine in the driveway, of course, when I can stand over it and listen.

Any Ideas?

tranny bearing or gear whine?

No, it a noise all on it's own. Doesn't change with regard to engine speed, rolling speed, in or out of gear...

I'm looking to see what F.I componants are on that side of the engine.

ignition components? i have heard whining CDI boxes......

Check your intake boot, your idle stabilizer hoses and generally any hoses on the intake side for cracks, splits, looseness.

It sounds to me (no pun intended) like you may have an intake leak that only shows up under full throttle conditions.

What air cleaner are you running?

It may just be a resonance of the intake manifold coupled with one of those cheap cone air cleaners.


Post some pics of your engine comp.

BTW, there is no CDI unit on the 3.2. Ignition is all controlled through MOTRONIC.

I agree with John, check the idle speed motor.

Maybe electric fuel pump or pressure reg ?