Thanks guys!

I wondered about the ignition retard function as I know the 560 does not have a knock sensor (usually good for about 10 degrees or so retard when signalling knock). However, all of the systems I've seen advance the timing to raise the engine rpm when too hot, retarding the timing usually makes them run hotter, not cooler.

Engine sometimes runs pretty good cold (especially if just worked on, to fool the technician), then goes "flat" hot. Low vac, very hot exhaust manifolds, late timing, sluggish performance. Timing does increase with rpm, though. Computer has been replaced (removed when the carb was installed, used one aquired when FI restored), so it's unlikely to be the computer.

Setting the mixture would likely be difficult at 20 degrees ignition retard due to lousy combustion, I would think.

Timing has been verified as 20 degrees late with engine warm.

I'll check in with Hans next week (more parts, like usual -- I think I keep their electric bill paid with all the stuff I buy!) as see if he has tested the temp sensors. I believe he has, but I'll suggest it anyway.

I personally don't put much reliance on what the PO says about never having the engine and tranny separated, unless he actually did all his own work anything is possible, including a shop fixing an error and neglecting to inform the owner.

I'm not very familiar with the crank position sensor systems -- is it possible for the pickup to be slow responding to the rotating flywheel tabs? A gradual voltage rise would account for the late timing, but I've only seen working or dead Hall effect pickups, never one that only sort of worked.

Would bent tabs on the flywheel cause the same problem?

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!