My '88 240 wouldn't start yesterday in the pouring rain. It would crank and crank and barely start to run, but with heavy sputters and shaking of the car. Even with gas applied (which normally is not required to start car) it would not continue to run. I pulled the coil wire off the distributor, and it had spark. I pulled the plug wires, and there was only spark in the first and third plugs, none in the second and fourth. I immediately suspected cap and rotor or plug wires, but since wires are $55 and cap/rotor are $15, I went with the cap/rotor first.

Turns out the parts store gave me the wrong rotor but the correct cap. I repaced the cap and it started fine, in fact better than normal. I drove it around, got it up to temp and let it sit for a few hours before trying to start it again. Didn't start. It was a little different then the first time, this time it would just crank and crank without ever starting to run.

I've gone back to the parts store and gotten the correct rotor, so I will try that. Any other suggetions?