Greetings..

When I first start my 96 850 turbo sedan it spins up to about 1400 rpm when you first crank it.... Anywhere above 1000 rpm when first started the driver can hear a strange moaning sound coming from the engine compartment. If driven cold this sound will get louder as the car is accelerated and fades in and out getting louder and softer in turn independant of speed. However if the car is allowed to come up to operating temp, the only time the sound will be heard is when it is first started and spins to to 1400 on start. At the idle speed of 900 rpm there is no sound and when warm, never any sound.

Thanks in advance!!

Is the noise a ghostly moan that only occurs in temperatures below 40F, that goes away a few minutes after start, and changes pitch with engine RPM? If so, this is rather common on 850's. I've read numerous posts on this board asking about it, but I've never read an explanation. It started on my '94 when the car had 14000 miles (in 1995) and continued to the day I sold it a couple of months ago. The dealer could never find anything wrong, so I learned to live with it. In my case, it was definitely not the air pump, oil pump, timing belt (including tensioner, etc.), or anything turned by the accessory drive belt.

air pump.....its job is to get your engine to proper operating temp faster. see archives for common problems and fixes
regards

Could also be your air pump, which runs for a short period on starting cold (on some models -especialy non-turbo I believe).

Hard to know without hearing the noise but faulty cambelt tensioner or idler bearing is posible and not too unusual.Also auxillary belt could be part of the problem,remove the drive belt and start the engine,if noise goes away then its one of the components driven off the aux belt e.g. A/C compressor ,alternator etc...See if it makes the noise when revving the motor in park or neutral without driving it.