Hello
I have a 1994 BMW 530i. With the exception of the paint (detailers have been washing it all wrong for a while) it is in excellent condition. I have a complete service record for the vehicle and other than some characteristic problems (like the radiator/waterpump) and some old age problems (leaking trans fluid) there really haven't been any issues.

Recently replaced: O2 sensor, spark plugs, spark plug wires

My problem is that before the car has warmed up, and particularly if I let it idle for >15s before driving it the engine idles a little rough, just enough to barely shake the car. A few times it would set off the check engine at a stop light with the transmission in "D" before it was warmed up, but it no longer throws codes. The car also shakes just a little (even less than when the car is warmed) when waiting at a stoplight with the transmission in "D." I have just been putting it into neutral to avoid this issue.

I tried the "stomp the gas" 5 times thing several times to see the code history to no avail.

Should I worry? Is there any trick to get the code history?