Distributor Timing
 

Help! What controls the timing on a 560 SEL? How do I advust it? Mine is at 30 and I can't get it to TDC by rotating the dist. A timing lite is showing 30 degrees advance at idol (~800RPM) on my 90 560SEL. It smoothly advances to ~40 degrees as the engine revs. Moving (rotating) the distributor doesn't change the the timing more than a degree or two. Car seems to run fine and the emissions are all very low. It passes smog, but the timing is too high.

On the Bosch CIS system,timing is controlled by the ECU, not any mechanical adjustment.

What do I need to do to get the timing correct, TDC? Why would it be 30 at idol?

Can anyone redirect this to Technical Discussion? I think that Garymand will have a better chance of a detailed response in that section.

... I used to be an idol, back when I was 30, that's when my timing was still correct ...