So, after I installed my boost gauge a few weeks ago I noticed a "squealing" noise from under the dash area (boost gauge is in the dash cubby hole). Only hear it above 15-20# and it gets louder as you get up in boost. I disconnected the line off the back of the gauge and the "squeal" went away- just lots of "pssssss" out the line. I also felt the gauge and around the fittings and there was not vibration or any air leaks that I could see or feel. Felt more like it was under or behind the dash.

SO.... Figuring I have a leak in the plastic tubing, I spend a couple of hours yesterday fishing new tubing through all the wire loom and hook up the new line (to a new gauge as well.. upgraded to a 60#) and SHAZAMM!!!

Squeal is still there and actually sounds a little louder now!!!!

I have sealed around the firewall hole with foam, so I know the noise is not coming from the engine compartment.

I'm confident there is no leak in the plastic tubing now. Any other suggestions what could be squealing as boost pressure goes up???

Thanks!

 

you use pipe dope or teflon tape on the fittings on the gauge and where you plugged it in on the engine? what did you use to tap into the boost?

 

I used a Geno's boost bolt on one of the manifold bolts just under the firewall area. Standard 1/8" compression fitting on both connections with teflon tape...

 

a tie wrap on the hose?