Jim:

If the Haynes manual wiring diagram is correct, this is an electronic relay, and therefore bad. Temp sensor is an NTC thermistor in the relay.

Re-adjust the valves after about 1000 miles before getting too excited about shake -- you may have uneven compression until the rings seat properly and the valves are completely lapped in, Cassidy Machine or not (they appear to do excellent work, by the way!). You will have to load the engine quite a bit to get the rings seated -- Hans recommends several long, steep grades in top gear at low speed, with dino oil in the engine.

I suspect that if you drive much like I usually do -- that is, I'm not a stop light drag racer by any means, you never really use the available power in most cars anyway, so the 240D isn't slow. I don't notice the 220D being "slow" except when I need to pull out into traffic, and I atribute most of that to the lack of a torque convertor in the tranny, not lack of horsepower. I also never found by 1970 VW to be grossly underpowered, either. May just be what you get used to!

Check the brake hose for one-way action before you replace or rebuild the caliper -- I've had any number of them have the inner lining come loose so that the line would hold pressure. Big pain, easy fix.

Also, check that the rotors are thick enough -- far too many people cheat on brake jobs and just toss in a new set of pads. The ATE calipers will bind if the rotor is too thin -- the backing plate on the pad hits the anti-rattle spring -- tilting the pistons, already too far out of the bore, and causing them to stick. Carried on long enough, the caliper sticks, seriously overheats, and toasts all the rubber. Can be cured by a rebuild kit (new seal, dust cover, and heat shield) if the piston and bore are still clean and smooth.

Do not hone these calipers, they are chrome plated. Any rough spots on the caliper bore or piston that cannot be removed by normal cleaning means replace caliper. I've also been advised to avoid aftermarket rebuilds, too -- they seem to nearly always seize.

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!