Pontiac Montana has VERY Hi pitched Squeal HELP!!!

[Frank]

Just replaced head gasket intake ,lower and upper and 6 studs on exhaust manifold. Got vehicle all back together and started and now emits a high pitched squeal like an air leak or exhaust leak. Seem to quiet down at low idle then starts back up again . I took car apart today and checked all exhaust connections and they are tight. I even torqued on them with a 1/2 in breaker bar. Before I take this thing all apart again or lose my mind and junk it . Does anybody have any ideas what I might have missed. please help 🙁

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[Frank]

I found the trouble .The guy holding the wrench. I installed the upper air intake gaskets upside down duh!! .They then acted like a reed in a woodwind instrument and created that lovely sound. Taking top off tomorrow and fixing gaskets. wish me luck Epic face palm

[Mike]

Good man, you’ve gotta own your mistakes. Good luck sorting it back out tomorrow.

[EricTheCarGuy]

Good find. I was going to suggest a vacuum leak.

Thanks for the update. Also, for your amusement.

[Frank]

😳 I did not install the gaskets upside down . But in my haste to put the upper plenum on I mangled the gaskets(Brand new). Replacement is only six dollars so not too bad. Mangled around bolt holes so I think I’m using to much torque. Any body know the torque specs? Going to get new seals ,wish me luck 😳

[Frank]

I am very happy to report that The Pontiac Montana is up and running the roads again like a champ. Purrs like a kitten. No more noises Don’t remember if Eric covered it in his “Cars that sit video” but if you let your car sit for a while check the brakes and do a thorough inspection of the vehicle. I not only found 2 frozen calipers but a hornets nest so be careful.

[Author]

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