I have a problem with my '86 5000TQ wagon.

Over the last few months it has developed a problem whereby the car sometimes wont start. I'll get in, turn the key and it will crank away all day but wont catch. At first I though it was fuel, so I tried spraying some quick start to no avail. I then pulled a plug, grounded it and saw that there was no spark at all during cranking. So, for some reason there is no spark. It has new plugs, leads, distributor cap and rotor. I have followed the proceedure in the manual for testing the coil and it checks out ok.

What's even more weird is that it's completely unpredictable. It will be fine for 2 months, I'll drive to work then at lunch it wont start. At the end of the day I'll get in and it starts right up. Yesterday morning it wouldn't start, today it did.

It will do it rain or shine, hot or cold, cold start or after it's warmed up. Is this a common problem?

What I have noticed is that once the car is running, it will never quit. It's just that innitial starting that is a problem. It's as if there is no signal getting to the coil that tells it to fire.

Anyone have any ideas? Anyone seen this before?

Thanks!

 

Might be the hall sensor in the distributor.

 

Ok, update.

I drove it to work this morning, and now at 11:40 it wont start!!??

This time I wanted to rule out the distributor, so I took the HT lead off the distributor side and left the coil side attached. I put a screwdriver in the open end of the lead and lay it across the engine. No spark there either! So if the coil "checks" ok, then what can it be? It's as if the coil is not getting the signal to fire. Is there a way of checking this? I removed the 3 spade connectors off the top of the coil and cleaned them up - but that didn't help.

Is there a way to test the hall sensor?

Thanks.

 

Go to SJMautotechnik and go to diagnostics link. I found the sight very helpful when I had intermittent problems with my distributor.

 

Thanks for the link!

I went out and pulled some codes. Normally everything is OK - but this time it gave me a 2113 which is "Hall Sender not getting signal."

Does that mean that the Hall sensor is bad or is it something like the crank sensor that is not sending a signal?

 

I would first confirm that your car has a crank position sensor as the factory manual is very fuzzy at best. On my 100Q the pulse signal from the hall sensor was missing and ignition ECU was not sending a signal to the transistor unit which in turn didn’t trigger the coil. A shot of “quick freeze” on the hall element might do the trick. When I went to a local junkyard I found many cars with the ECU units but no distributors. This leads me to believe that it is a fairly common problem.

 

Very good point. Especially as a new Crank sensor is over $200.

Now, I have a spare distributor - but here's the issue. In '86 there were 2 different types of distributors - one with a fat centre post, and one with a thin centre post. The one on the car has a fat post, and the spare has a thin one. Is the Hall sensor the same for both? If so, can I simply put the hall sensor from the spare one onto the car?

 

A remanufactured distributor runs about the same as the crank sensor. I don’t know the difference between the two distributors that you mentioned could be just the connector. I know that some 5000 distributors will fit and work in 100/200 models. I found a remanufactured unit at a junkyard that used a Siemens HKZ101 hall element and that is what I have been using. The distributor is somewhat of a pain too pull apart but possible, all you need is a Dremel type of a rotary grinder and a pin drive punch. If the Bosch numbers match on the hall element then you should be OK. In my search for the hall element I have discovered that just about all the Bosch distributors had the same hall element. So one from a Volvo, BMW, VW, Saab, etc will fit and work.

Do a search for the Siemens HKZ101 and you will find plenty of info.

http://www.cy-sensors.com/Vane%20Sensors.pdf

 

Ok, I may have solved the problem.

The car finally started at about 8:00 last night, so I was able to drive it home. When I got home I searched around my basement and found an old used distributor that worked when it was taken off a parts car. I hauled out the old one, and put the new one in. The car fired right up and runs smoothly! Now, it could be that the car is just in one of it's "I'll start today" moods, and this distributor is as good as the one I took off, and the problem is something else.

But I hope not. The electrical connector on the side of the distributor I toook off was just hanging there. The plastic mounting tabs were all broken and all manner of water and woodland creatures could get into the distributor body - not to mention the 3 exposed wires. They probably had a poor connection somewhere. That's what I'm hoping anyway!

Thanks for all the help and I'll post if the problem returns!

 

I had this same exact problem with my 87 5000 CS QT and I had to have my distributor replaced. The mechanic was going to do a rebuild it but he could not get all the parts. I had my fuel pump replaced as well due to a bad diagnosis by another mechanic, wasted $$$.