I have a 95 venge ES...when i start the car and it's cold outside i have this very loud squealing noise..especially when the heat is on...but sometimes that part doesn't matter..and after the car has ran for bit then the squealing goes away...wondering if it could be the drive belt idler pulley...bushing going bad on it?.. or if it is something else. Another problem i have that im not sure if is related is when it idles cold...the rpm's tend to go up and down a bit..like around 500 rpm sometimes...up and down...up and down....when it's cold. any help would be appreciated, thank you.

 

It could be a loose belt , when it's cold it slips , when it warms up the rubbers tackier and stops the noise ,,,

The idle variation can be a dirty intake tract/ bad IAC / or Bad EGR

 

thanks...im going to check the belts and clean out the system...hopefully it will help.

 

ok so this just happened to mine...fixed. it was the a/c belt tensioner pulley. the bearing in it completely seized up and the pulley had started to spin on the bolt instead. i pushed the bearing out of the pulley and pulled off the seals. after about a 5 min varsol bath with a toothbrush the bearing was free and spun like mad. I regreased it and put the seals back on, pushed the bearng back intothe pulley and it's good as new. Have a look at yours, maybe it's the source of your noise.

 

it could be the source of your rpm surge too. a seized pulley will strain the engine.

 

Chances are that if it were the EGR valve a code would be set, the same for any sensor. The pully could in fact cause a strain in the engine, however 500rpms sounds a lil too much for this to be the cause.. GL

 

Actually when my EGR went it never threw a code at all. The only time it did is after I blocked it off, which fixed the idle problems.

 

that's a lil diff. than what i am used to.. usually when the egr diaphragm is stuck it will shoot a code that tells you that it is not getting enough air flow. I had a Dodge neon once that had a bad egr valve, and once i replaced it, it actually ran worse than with the bad one.. lol