Replace the rotor and wires, too, and check the plugs. The rotor wasn't in any better shape than the cap, after all.

If the check engine light didn't come one, the bulb is burned out.

The wires failed when you replaced the cap since they get brittle with age, and cracked, possibly breaking the conductor too, and I would bet you have a couple of them swapped around, so some cylinders aren't firing. Should be marked on the cap if you look closely. They must be in the correct order and position on the cap.

DO NOT drive it in this condition, the catalytic converter support will melt and plug the exhaust, to say nothing of setting the car on fire (no joke!). If the chain jumped, it will soon break and you will definitely be out a $4000 valve job.

Yes, it could be a timing chain jumping, in which case you need to re-set it and replace the tensioner -- although it is also probably worn out and you need a new chain anyway (they don't jump unless WAY long).

Worst case you jumped the chain and have now bent the valves, but they usually won't run that way.

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!