Okay so this sound which I at first thought was like a rubbing rubber sound like the belts has been going for a couple days now. I removed teh AC and PS belts and the noise persists. I realigned my air pump because it had turned a little and the belt was at an angle and the sound is still as loud as ever. My car is an 87 N/A and it idles a little over 1k its done that since I bought it but this sound just started. The sound increases in pitch from about 2.5k and keeps going all the way up. Its almost like a skreeching sound but it also sounds like the engine is maybe sucking air, also when I let off the throttle between shifts there is a sound like a BOV releasing pressure. Im thinking it could be a vaccum leak or maybe a bearing but please let me know what you think the sound is so loud I dont want to drive my 7 because I want to keep the good image of it.

 

might b ur waterpump

 

Just that the waterpump is bad or the bearing in it is shot?

 

They're one in the same. You can't replace a water-pump bearing to my knowlege, and for the price, you wouldn't want to if you could.

What you should be able to do is to take off the belts, and start spinning components. Spin the alternator pulley, the water pump, the PS pulley and tensioner pully, as well as AC and Air Pump if you have them.

I'll bet one of your bearings in the pulley is going.

 

you probrably overtightened a belt and killed a bearing somewhere

 

That may be possible, the air pump was at a wierd angle and it required me to use spacers to fix it so it was parallel with the drive pulleys and maybe the bearing in that got all messed up, but after I realigned it today it still makes the sound, the alternator also looks pretty new so im guessing its been replaced and I think I remember the guy telling me hes had to replace the alternator a couple times. I tried spraying some carb cleaner around to see if there were any vac leaks but I couldnt find any and the nipples I found all had good plugs on em unless its a leak under the intake manifold but I am not really having any idle issues. Just to cover my bases would a vac leak make this sound also? or perhaps some how a leak in the gasket for the intake manifold? If it is the air pump I will be getting rid of it once my RB exhaust comes in. Thanks for your help.

 

Oh one more thing though, I bought a mechanics stethescope and listened to the alternator,waterpump, and air pump and there seems to be no irregular sound, the air pump and water pump give a flowing air/water sound and the alternator just sounds like its rotating fine that makes me more suspicious of a possible vac leak.

 

any hoses predisposed to failure over others I should check or that are under the intake manifold?

 

Could it be a bad throwout bearing squeaking or is it comming from the motor? When i first put my new clutch kit in the throw out bearing squeaked a little mimicking a belt squeak but it was like a mouse noise, nothing bad. It eventually went away

EDIT, nevermind i just finished reading your post and saw the part about teh blow off valve noise and all. I guess i should read the whole thing ehh

 

I've been hunting for exhaust leaks and one thing that might help you localize a sound is a hose or a tube.. I just took the hose off my shop vac, and pointed around with that (the other end up to my ear) to find stuff.

May or may not help...

good luck.

 

The guy that had my turbo 2 before me didnt put the gasket back in btwn the upper and lower intake manifolds and it made some loud hissing noises (engine was F'ed and wouldnt idle by itself when i got it) if it has anything to do with the intake gasket you could be running lean so you should check that out.

 

My idle is fine though and I tried to find exactly where the sound is coming from but I can't seem to find one area that is coming from. It's a hard sound to explain but after about 2.5k its like a very loud sucking/rubbing sound that increases with the revs till like 3.5k then maintains the same pitch all the way to redline. Its not the bearings in any of the accessories and the vaccum hoses i can see look like they are in good condition. What vaccum hoses could cause this loud of a sound and are they under the intake manifold? or could an exhaust leak cause this sound?