97 FM S1 Kit High Pitched Squeal
 

Hello all,

Just need a bit of guidance on where to look next on a high pitched squeal heard from the passenger side (not belts) that ONLY happens when in boost. I'll save you the entire story and just give you the cliff notes.

1997 NA Miata @ 158k
Complete FM S1 Turbo Kit w/ included piggy back
FM Happy Meals Clutch Kit
FM Coolant Reroute
New belts
New slave and clutch master cylinder w/ SS braided lines
New NGK's @ .025

The only thing out of the ordinary I've done during the install was remove the charcoal canister, as it got in the way of the reroute and radiator. So the Evap solenoid is looped together. The EGR system is still installed and intact. Any other ports to the intake mani are capped off.

During driving at WOT, the AFR's sit at 10.5:1- sometimes creeping up to 12.5-13:1 right before shifting. However, the "squeal" is heard as soon as the boost gauge hits 0 and is audible throughout the entire 6-7 psi boost range.

I thought it almost sounded like a belt in the beginning, but not as intense and not connected to RPM speed. Only while in boost- doesn't change pitch or tone. Just stays constant. Still- I replaced the belts since they got a bit of antifreeze on them from doing the reroute but the squealing sound remained. Thanks in advance for your time.

Is it possible for one of the pullys to squeal under boost? I'm pretty stumped. I rechecked and tighted all the tbolt clamps and I made sure to use thick double sided tape on anything that might rub during boost. I'll keep this thread informed of what I eventually find.

Check for missing vacuum plugs on the intake manifold. There's one on the bottom rear of the bp05 intake manifold that has given me trouble before

Ports on the intake seem fine. Ive spent the last few days messing with the vacuum lines to no avail. I guess I'm at that point where I upload a video and play "whats that noise" with you guys.

I've verified all clamps are tight and not in contact with anything or is padded up against something. Ive sprayed carb cleaner around the intake mani and found no leaks.

I'm about to the point where I start removing stuff to see what changes.

I'm pretty sure it was the EGR tube not being cinched down on the intake manifold. There was about half a mm of gap between the intake mani and the egr tube. No more sound- just quiet boostttt! Thanks all!

I had a bad alternator making a racket for some time before I figured out what it was.