High pitch squeel ... need help

My wife has a 90 automatic. IGOCOMMANDO showed me how and did a tune up on her car not too long ago. Did the plugs,caps,rotor, ran some seafoam through it and all. It had/has a known exhaust leak. My wife noticed these past couple days that there was a high pitch squeel coming from the engine bay. It's not always constant but comes and goes... so when I got home from work I started it up... ran for about 5 minutes and no squeel. Turned it off, waiting a few seconds and started it back up. Now this time I could hear it and kinda pinpointed where it was coming from. These pics are the area where the whine is coming from... any ideas what this could be?






That's the general area where it's coming from...
Thanks!

tighten the intake/ exhaust manifold bolts. Same thing happened on my buddies rig.

Well I see the fuel rail in the area where you are highlighting is it only during an idle speed or all speeds? It is one possibilty that the injectors are the cause but I can't be sure what it is since I am not there. Also how are you locating the noise? A stethascope with a long tube will help you isolate to the exact spot. Hope this helps.

Maybe a vaccume leak. SOmetimes they sound like they come from one area and arent even close. It's hard to pinpoint when the other noises of the engine are at play.

I had a vaccum leak at a t-intersect to the cruise control diaphragm and I swear the sound was coming from around the brake booster...

Sean

Spray soapy water onto it all and look for bubbles. Let us know what you come up with:scottm:

intake gasket seems most probable, but check around the throttle body as well-- both would have greatest vacuum on them when throttle was closed (idle) and would manifest themselves as described

--Shorty

Since its a high pitched squel, i would assume that its the vacuum line from the MAP sensor to the throttle body. I dont think the intake / exhaust manifold bolts backing off (although its a common problem) would cause it to give a squel that is high pitched. If it was me, i would check that vacuum line first, then make sure all the bolts for the intake exhaust manifold were tight.

Thanks for the replies. When I was at IGOCOMMANDO's he had me tighten all the bolts on the intake manifold... I'll recheck them though and i'll check the vac line. Like stated before, the noise comes and goes. At idle it's pretty loud, when I open up the throttle it goes more into a faint high pitch. It's not going to have any short term damage to the vehicle will it?

Bdiddy11 said:

Thanks for the replies. When I was at IGOCOMMANDO's he had me tighten all the bolts on the intake manifold... I'll recheck them though and i'll check the vac line. Like stated before, the noise comes and goes. At idle it's pretty loud, when I open up the throttle it goes more into a faint high pitch. It's not going to have any short term damage to the vehicle will it?

Click to expand...

Sounds like a vacuum leak. Check all your vacuum lines big & small.
Earlier in the thread you mentioned you SEAFOAMED IT... Did you put it in the Engine via a vaccum line? I had a similiar issue with my XJ too. All the hard plastic lines looked fine, but when I went to slightly bend one of them.. I noticed it was cracked and this is what caused the whisteling.

Ya we Seafoamed it with the vac line by the big brake booster or whatever it's called on the firewall. In the pics, it would be to the right of that area by about a foot give or take... i'll check when I get off work.