'92 735i idle problems

So I picked up a new (to me) '92 735iA after a 7 year hiatus since my old 733i. It's generally running very well but feels like it's idling too fast and too rough. In neutral it's sitting at around 800 RPM and in drive sits between 800 and 1000. Feels like it would more natually be down towards 650 in gear. Am I just imagining things?

If it's too high what might be the cause for this? It's not manually adjusted high (by virtue of the throttle cable). That adjustment appears to be as low as it will go. It seems odd to me that the idle won't manually adjust below 800RPM in neutral. In addition it feels a little bit rough on the idle, particularly when the AC is on. I know these engines tend to be a little rough on idle but this feels exceptionally so. Any thoughts on what might cause a higher than normal, rougher than normal idle?

I'm rusty at this (after 7 years away from BMWs and most things mechanical). Any input would be appreciated. Thanks.

your troubleshooting might be a little though without any history on the car.....sounds like someone's 'tinkering' to mask a problem [low/rough idle] for which there can be a number of causes.
Your idle speed hunches are correct, it's too high.
First be sure both throttle cables have sufficient freeplay[ moving the cable won't open the throttle]
then look at the 'factory set' idle stop screw for signs of tampering. also check for broken, cracked or missing air and vacuum hoses. Any documented history you have might also be of help............I'll be
arround.................best to you....................jb.

Thanks Jeffrey. I'll check on those things tonight. My Bentley manual is on order so as soon as that shows up I should have a better map for searching out the issue. I appreciate the direction.

Thankfully the factory idle was not tampered with. I found and fixed a loose connection on the vacuum hose between the MAF and the intake manifold. In addition I changed the air filter which was pretty gunked up and ran two bottles of Techron fuel system cleaner through. Car is running much better now. It's idling about 750 (800 in gear) and much smoother. Still not perfect but close enough that I think it's off the list for now.

Thanks for the suggestions.