Car Start/Idle Problems.

Hi,

I have a '94 BMW 318i - Manual Trans. I purchased from Germany and its German Spec.

When I start my car, its not a good solid crank - somewhat of a "weak start".

But it somewhat starts and the idle rpm dial barely moves up then it fluctuates up and down around 500
+/- 100. Then the dial on the rpm gauge will start dropping slowly then it will pop back up to around 500. Other times it will just go so low and wont come back up and just kill the engine.

--I've notice this happening when I drive my car for long periods of time or within several hours of me starting my car back up after leaving it sit.
--When I leave it sitting for like around 8 hrs or more it seems to start fine 9 times out of ten.

When it starts doing what I said it did above I just start it and give it a little gas and hold it down for like 30 secs, then slowly release the gas and it steadys around 500 rpms. I've also notice that it makes a funny squeaking sound when its at idle and I dont give it gas, once I get going it stops.

Please, any suggestions are appreciated. Thanks.
-Ken