Help - noise toward front of engine
 

Whirring type noise that accelerates with engine speed but disappears when she is warmed up /driven. This has been going on in past but mostly when it was cold in Spring, but now it's there almost always at start-up until it's driven a while. 1986 944NA . Otherwise runs great /quiet etc.. I feel it probably does not get driven enough.. Any comments/clues appreciated. thanks

Balance shaft belt?

You are now officially off my "trust list"..
;)
(Just couldn't resist)

I just got off 12 hour watch and am shooting in the dark lol

The next time you start the car lift the hood and look to see if the fans are running. If they are, turn off the A/C and see if the fan stops. If it doesn't, pull the fan circuit breakers. Then If the problem is gone then It sounds like you could have a problem with the fan relay or wiring.

If the fans are not the problem, since you said that it appeared they increased with RPM, then I'd look at the serpentine belt that runs the alternator and the A/C for tension. If it's ok then pull the front belt cover and suspect tension on the balance belt. Also, when was the last time the belts were changed (years/mileage)?

thanks fpor response - belts done about 10 thousand miles ago but that is maybe 9 years so I suppose possible issue. they look OK but yea they are old.. the fan discussion I did not follow - my fans come on when the motor is hot as they should. I am talking about the noise being there when the car first starts and is cold...

I was just trying to determine if the fans came on when the ignition switch was on and the engine was cold. This was to isolate the fans from something else like the belts. As far as the belts are concerned, about 5 years is the recommended service life. If the car has sat for a long time, they deteriorate faster as the rubber ages and they're kinda like tires that have sat in one position for a long time.

It just sounds like a loose belt warming up and then not making the noise... Like when I had my A/C belt too loose after it stretched out after install of a new one. P.S. change all your belts!!! They're way too old!