Question for everyone. This is driving me nuts.
Going down the road the car just quit. Now it will not restart.I've replaced the Radio Suppression relay that didn't work. I've replaced the ignition control unit behind the air filter assembly. Still no go. I can smell fuel after cranking the motor so I'm assuming I'm getting fuel. I do not believe I'm getting spark.

I've read the FAQ and tried a few things. I noticed that the tach jumps when I first turn the key on, but does not move when I crank it over. Also I have tested resistance at the coil. The primaries show 1.2 ohms and the secondary shows 7.6k ohms. I've taken the coil wire that goes to the distributor off and had my dad crank it over. I did not see a spark.

Is the coil bad or did the hall sensor die. This car as 280K miles on her. I'd hate to get rid of it. Its been a reliable car up until this past week (it blew the heater control valve apart and blew the upper radiator hose neck off both at separate times).

Thanks in advance.

Chris H

Pull the coil wire off the cap. Put the end somewhere that it's near a ground, but not touching metal. Turn the key on. Now turn it off. If the coil is still getting power and still functional, you'll get 1 spark.
The coil resistance can also be checked with an ohmmeter (multi-meter).

My suspicion is the hall sensor. You may be able to get it to run by wiggling the bottom harness connector to the distributor while someone cranks the car. IT could be shorted out. I bet you will need to replace at least the hall sensor. I had to put a complete distributor in my 88 last year. It solved the identical problem, and never had a problem starting since then.

It is also possible that the ignition power stage has failed, but I think it's less likely. Try to get both items in a junkyard to save $$$.

Good luck!
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Rob Bareiss, New London CT ::: '87 244DL/M47- 221K, 88 744GLE- 202K, 91 244 181K, 88 244GL 145K

If hall sensor is bad, the fuel pumps will not run. Listen for the main pump under the seat. Other quick test is to listen to the injectors. They will not click if hall sensor is bad. Not a difficult fix if yuo need to do it. Just be carefull with the fiber washers on the distributor shaft.

Did you check to see if the timing belt is good = cam is turning? Pull the oil filler cap and watch as helper carnks the engine.

Good luck

Dan

When I turned the key to the on position, I heard the main pump turn on for about 1.5 seconds. I pulled the rubber inspection plug on the plastic timing belt cover and did see the belt move.
I will check the injectors and do a visual on the cam through the oil fill hole. Is there any way to make sure its not just a bad coil without having to purchase it and replace?

Chris

If you checked the timing belt throgh the acces hole, there is no reason to check the cam. This indicates that the timing belt is good and therefore the hall sensor in the distributor should be seding pulses.
I think the 1.5 second on of the fuel pump is normal. The is a very good description of the start up sequence in the FAQ or archives. That is how I found that I needed a new hall sensor.
Dan

The coil can be also be checked with an ohmmeter to see if it is open. The most probable cause is the hall sensor, and the engine may to try to run with a bad one, but it will not remain running (driveway experience with 87 740). Also, the wires are easy to break or short so look closely. The second choice that it could be spark amplifier (Coil driver) mounted on fender-if you get one from junkyard, take the base plate as it needs the heat sink compound between the module and plate and most of us don't have any on the shelf.
Your info on the tach action points more to hall sensor IMHO.