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High Pitched Squeal On High Rpm / Boost

Everlong-S13

By Everlong-S13,
in Engines & Forced Induction

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sonicz Rising Star

sonicz

Posted
Posted (edited)

I recently changed my drive belts and now when the AC turns of at around 4000rpm and back on at 3000rpm it sounds like a massivley loud cricket as the AC engages.

I wonder if this is doing any damage as it never happened before. Belts too tight too loose?

Does yours do it with the air con set to off as well?

Edited by sonicz
Jayden.K Collaborator

Jayden.K

Posted
Posted

I had pretty much the same problem as you have. I had checked all the gaskets and still could not find the leak. It was also happening at 7psi and above. I had replaced all my vac hoses & all new clamps. Finnally I made this up and found the leak in about 5 mins.

Remove your intake from the front of the turbo, Attach the hose with valve to the front of the turbo, pump up using compressor. (no more than 10 psi) You should be able to hear the leak.

(Engine off, It will not hold pressure long. Just enough to find the leak)

Parts used to make this are

1 right angled silicone pipe from old stock intercooler pipes (or from any auto store)

1 screw in tyre valve

2 hose clamps

1 plastic pvc end cap (bought from a plumbimg store)

pressure testing the intake on a turbo car is by far the best thing you can do, you should make a pipe the has a t peice with a boost gauge and a compressor nitto fitting and valve. done this to my car, it was tuned with so many leaks that when they were all fixed the car leaned out across the rev range and wouldn't drive and had to be tuned again. you will be surprised what can leak under pressure, but when your testing have soapy water ready and you will see bubbles from the leaks. so much power can be lost from pressure leaks

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