Okay first I would like to say I did a search and didn't come up with the same symptoms.

Okay on initial startup either early morning cold or late afternoon warm weather I get a whining noise kind of like sreaching sound coming from under the car maybe around the tranny area. At first
I thought maybe belt tension pulley like mentioned here but it only happens on rpm 700 to 800 maybe 900 rpm. So while warming up on neutral screaching is there, when you rev a lil from 700 rpm to like 1000 rpm and you do here the sound get a lil loud (could be pulley at this point) but once you put it on drive and drive of stepping on the gas heavy or lightly the sound isn't there it goes away (so if its the pulley I should here this get louder as I rev the rpm either neautral or drive right?) I thought maybe tranny fluid is low so I checked and it was low 1/2 a quart so I refilled it but the sound is still there on warm up. Please help guys not sure where to start.
thanks in advance.

 

Turn off the climate control completely, and see if the noise is still there. If it disappears it could be the air con compressor.

 

You might want to tell what type of car you have and post in the tech area for that model.

 

Sorry guys its a 1995 xjs

 

Didn't help at all still there.

 

OK, post in the XJS forum so you get more XJS experts looking at your problem. There are a number of bearings in the engine ancillaries like alternator and belt tensioners. These bearings fail, so it is a matter of detective work to see where the noise emanates from. This can be very difficult even for an experienced mechanic.