Help! What controls the timing on a 90 560 SEL? How do I adjust it? Mine was at 30 degrees advance at 950 idle . It smoothly advances to ~40 degrees as the engine revs. Car runs fine and the emissions are all very low, passes smog, but the timing is too high. R16 sets timing with no vac on EZL. I changed it to get 0, but vac on, gets it back up to about 30.

I cleaned Idle control valve, removed andblocked the bypass at the ICV to get 850 idle and 20 degrees. I think this means too much gas. The ICV current is about 600ma. fairly open?

Adjusted mixture 1/2 turn CCW to get 650-700 idle, (in spec), but timing is still 12 with vac on. Its 0 tdc with vac off. duty cycle voltage is about 4.1VAC 70%? I put the 750 ohm R16 back in to get about 7 vac off 12 vac on.

X92 LED never flashes. LED comes on when button is pushed with engine running. engine off, ignition on LED on, button does nothing.

Any ideas?