I have a 1990 740 with 200K miles. It runs fine at 10 MPH and above and when warm. However, cold starts cause very, very rough running for anywhere from 5 to 10 seconds, then all of a sudden the roughness goes away. During the rough cold starts, if I give it alot more gas, it can actually stall, but if I lightly tap the gas pedal it keeps running and then it is fine, except that it shakes and rattles at idle when in gear, but does not stall. I have taken it in for servicing and will be doing so again in a few thousand miles, but am trying to determine what is causing this problem.

While it's always good maintenance to keep your throttle body clean, you might also want to clean or replace your idle air control valve. They get gummed with oil inside, and sluggish in cold weather. If you have Bosch injection, the IAC is Bosch. If Regina, it's a VDO. My '90 740, Regina, 170 K, had the same winter symptoms. I removed the IAC valve, sprayed lots of carb cleaner inside, held thumb and finger over the air openings, and shook vigorously. Repeated this numerous times, then, with the ignition on, kept plugging and unplugging the elec. line to work the piston back and forth, further loosening crud. Did this maybe 20-30 times, then cleaned and shook it out again before reattaching. The first couple of cold starts afterward, it was more balky than previous, but subsequently the stumbling diminished markedly, though it's still not perfect. Replacing a dirty valve is the surest option, but can be pricey. Bosch units appear on eBay occasionally. I believe the FAQ also has a section on cleaning these, a trickier operation.

Clean the throttle body. That should improve the rough running.
The shakes probably won't go away unless you change the engine mounts, which are shot on every 740 on the planet. Including mine.
--
Rob Bareiss, New London CT ::: 86 244DL, 87 244DL, 88 744GLE, 91 244: 808K total