My little '86 240DL manual wagon (Simon) will not start. The first time I noticed it was in late October. The engine turns, but does not start. I am pretty sure it is not exclusively a starting problem because it was successful 2 times since Oct., but proceeded to stall 15-20 minutes later on both occasions. Could not restart. I have determined that there is fuel at the injectors and spark at the plugs. Does anyone have a clue on what might be wrong?

Symptom summary: Rare starting. Runs great when start is successful. Stalls whenever running for 15-20 minutes.

A lot of people tell me that it's time to get a new car... but none of them have ever owned a 240. I love this car and am willing to spend my time and money to get it running again.

I suspect a short in the wiring harness. As you may know from reading this board, 82-87 240's all have a problem with the wiring insulation. The insulation rots and falls off allowing wires to short out. The first wires to fail are the ones (usually 5) coming out of the gray plug at the firewall. One of these wires carries 12 volts from the ignition switch to the ignition coil so if it shorts out, the engine dies. As a test, connect a jumper wire from the positive battery post to the positive coil terminal 15 (disconnect the harness wire from the coil before connecting the jumper) and try starting it. The wires from the gray plug are easy to replace.

The first and easiet thing to check is the condition of the 25 amp fuse located near the battery. Its relatively exposed and close to the corrosive fumes of the battery. Overtime the white plastic deterioates and the contacts become resistive. Can easily be replaced with a waterproof one and packed with die-electric grease.

Unfortunately, the 25A fuse was not the source of the problem. I wish it had been, because that is a pretty easy fix. Thank you for that suggestion, it is something that I had not previously considered.

Any other ideas??

One thing that I suspect now is the temperature gage sensor. Today I tried to clean the leads and noticed that the lead on the sensor itself seems to be a little loose. Before I open a can of worms and decide to replace the temp gage sensor, does anyone know an easy way to test it without removing it? Also, are the symptoms that I originally described indicative of a faulty temp gage sensor? (I believe what I'm talking about is the temp gage sensor. It is different from the temperature sensor. It is the sensor with one red wire attached just under the intake manifold at #2.) Thanks!

The gauge sensor will not affect engine function. See the FAQ under engine sensors for how to test the Engine Coolant Temperature Sensor (ECT) which will affect the engine.

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David Armstrong - '86 240(350k km?), '93 940T(270k km), '89 240(parts source for others) near Toronto