Non-starting W123 280E, ignition?

[bobtailbun]

Newbie, hello to all. My first post -
1984 280E, started as usual first time. Warmed up and then stopped dead along street. Seems to be fuel to system, no spark at plug. I have followed MB manual and checked ignition system with meter (breakerless/no resistors), apart from dwell -which I can't check. -
the symptoms point to the ignition distributor. I would have guessed at the ECU, but the fault chart says, distributor.
Is the only remedy replacement? Has anyone else had this problem/what cure?

thanks , Bob.

 

[Dieselman]

I'm not particularly familiar with the system on your car but assuming it has a normal HT distributor and the coil is fired by the ECU then a simple test is to disconnect the king lead from the distributor and stick a screwdriver into the lead connector.
Holding the shaft of the screwdriver about 25mm away from the engin have someone crank the engine. There should be a spark to the engine.

Assuming there is a spark then the problem must be the distributor cap or rotor arm. Replace.

If there is no spark then suspect the coil. A quick test is to attach a piece of wire from the coil -ve connection and rub the other end on the battery negative post or engine.
This will activate the coil just like the ECU does thus creating voltage on the HT connection.

A quick method of checking for sparks is to either hold an HT lead whilst cranking or to crank the engine whilst watching the HT leads in the dark. You will either feel or see the spark.

Warning!!
Don't hold the HT lead if you have a weak heart or a pacemaker and only use your right hand with your left behind your back. 40kV is a helluva belt!!