Did some work that seems to have cleaned things up for me.

thouroughly cleaned the automatic Idle Air Controller and the the throttle-body, and ensured vaccuum lines were fitted well and cleaned up so I could see cracks and bends.... the idling problem seems to have evened out. I think it still sounds noisy but my engine has the characteristic b230 pistion slap noise that makes the engine tappy anyway. My pops thinks I'm just being paranoid now because I'm overly sensitive due to the problems I was having.

Anyway, here's a tip for anyone pulling their IAC to clean it that I would have liked to have my hands on before I got into the job:

The IAC is mounted on a bracket which is bolted to the intake on the top and the block on the bottom.(Or so I thought) The rubber shocks for the IAC were broken and I couldn't get a good handle on it to unbolt the clamp and slide it out, so I just took the whole bracket out. BIG MISTAKE. The bottom bolts on the bracket are actually holding the engine mount bracket to the block as well. After I got them out (they came out surprisingly easy) the engine block slid down relative to the bolt holes in the bracket, so now I can't get the bolts back in.

Save yourself a lot of trouble and spend the time working on getting the IAC out of it's holder and don't take the bracket out with it. Stupid me....

The belt will only jump if the tensioner is very loose, which is pretty unlikely unless you forgot to set the tensioner? If you check the ignition timing with a timing light you'll see if it's wrong, indicating belt slip (the new belt, if fitted correctly, won't have changed the timing). Then you can rule that out and move on. Regards.
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BillB

Check that the coolant temp. sensor connector is properly plugged in. It's the sensor under intake manifold runner number three (under the intake-manifold section closer to the back of the engine). If this is disconnected, the car runs very rich.

Noel

Doesent the distributor run on gears for the timing, hence the timing belt actually runs the valves on the 740 (the middle gear does not connect to anything in the engin like the 240) hence my car was running before i owned it with the valves set wrong, but not the timing??

Eric
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89, Gold 745 GL Wagon, 210k known miles. Just a beginner

I am not sure of your problem, but on my first belt change, I put my new belt on like my old one, and it was at least five teeth off, it ran ok, it ran better when I corrected it. Something else may be leading to your running problems, are the plugs fouling. Mine was and the O2 sensor was bad, and it kept feeding fuel to the fire so to speak.
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89, Gold 745 GL Wagon, 210k known miles. Just a beginner