TheSamba.com :: View topic - ignition control unit location on 88 hard top?

Tue Mar 17, 2015 7:09 am

So long story short is that my van turns over but wont fire. I've replaced the coil, distributor cap, rotor, wires, and plugs. There's no spark at the distributor. I now have a brand new ignition control unit but I can't find the damn thing or any solid info on its location. I've looked in the engine compartment, under back seat by the brain, under the dash on both sides and other random spots. My buddy and I both looked online for a good while and couldn't find anything. I realize that it might not even be the problem but since I have it I'm gonna try. So can anybody give me a solid answer on where this thing lives? I'm at a loss here.

Tue Mar 17, 2015 7:36 am

edit.. sorry thought you were looking for the coil.

I'm not expert by far on the WBX's but I've never heard of an ignition control unit on a 2.1, assuming your engine is a WBX. Do you have a link to a picture of the part you bought?

Tue Mar 17, 2015 7:40 am

Not sure if this helps....

..on my 85, the ignition control module is bonded to an aluminium heat sink mounted to the engine bay body, driver side, just forward of the coil.

I assume you mean the black box, roughly 2x2 inches, 1/2 inch thick.

And to further confuse your troubleshooting efforts, it could be the Hall sender in the distributor as well...

Please forgive me if the 88s are totally different...

Tue Mar 17, 2015 8:00 am

I don't remember anything like that on our 86 (should be the same as a 88 model).
I might be wrong, are you this ignition module is for a 88?

Tue Mar 17, 2015 8:08 am

The ignition control for the Digifant system in incorporated into the Digifant ECU. Have you checked out the wires to the Hall pick up? They are tiny and overly brittle and thus are a common point of failure.

Tue Mar 17, 2015 8:27 am

Just a tip to the OP. As others have stated the hal unit is a likely culprit. However in my personal experience with a previous van, I was having a intermittent spark issue which turned out to be the ECU.

A trick I learned for checking spark, is to use a timing light if you have one. Hook the timing light to the coil wire and wire trigger open. This way you can see if it's sparking intermittently or not at all. This is very handy if you are working alone.

Tue Mar 17, 2015 11:03 am

OK so a little update. This morning it fired up, I drove it to the store, it started when I left the store but then died on the way home. I've looked in the engine compartment thoroughly so it's not there. I'm aware it could be the ecu but I want to make sure its not the engine control module since the ecu is spendy. This thing is very frustrating to locate. OK and a dummy question: what's a hal unit?

Tue Mar 17, 2015 11:38 am

The Hall unit is the electronic pickup in the distributor. You don't have a separate ignition control unit assuming you have an '86 and later US spec van so no use looking for it.

Tue Mar 17, 2015 12:00 pm

Wildthings wrote: The Hall unit is the electronic pickup in the distributor. You don't have a separate ignition control unit assuming you have an '86 and later US spec van so no use looking for it.

Thanks man. Ya that's what I was just told by north-westy. What sucks is I already bought the part. Oh well, its all a learning experience. Is the hal unit actually in the distributor? Because there's a part on the side of it that I'm not sure what it is. My buddy said its the condensor but he's not a VW person so not sure.

Tue Mar 17, 2015 12:02 pm

Shaunzo wrote: OK so a little update. This morning it fired up, I drove it to the store, it started when I left the store but then died on the way home. I've looked in the engine compartment thoroughly so it's not there. I'm aware it could be the ecu but I want to make sure its not the engine control module since the ecu is spendy. This thing is very frustrating to locate. OK and a dummy question: what's a hal unit?

Sounds like a wiring break somewhere. I'd check your wires at the hal unit as others have suggested.

The hal unit is on the side of the distributor. It looks something like this in the above picture and has an electrical plug which connects onto it. The wires on the electrical plug are often very brittle and cracked which cause loss of spark in many cases.

When mine had a issue with the ECU, it was only at start up. Not saying it will always be the same, but when my van had intermittent loss of spark related to the ECU it would run just fine "once it started".

Not once did it ever lose spark after it was running. It was always a issue of getting it running then it was fine until I turned it off.

Tue Mar 17, 2015 1:24 pm

Guys, its a "Hall" sensor - that'll help you when you're trying to look it up. ;)

Tue Mar 17, 2015 1:40 pm

There are two volumes to download but this one lists procedure for diagnosing a no spark condition.

http://www.loam.org/vw/Vanagon/VanagonProTraining/FuelSystems/

Best to print it all out and carry with the Bentley.

Dave

Tue Mar 17, 2015 2:10 pm

So ive got a new distributor ordered that comes with the hall unit. The screws holding the old one on are stripped bad so I just ordered the whole thing. The old unit has no broken wires but its pretty beat up so maybe thats it. My van should run nice after all these new parts haha. I'll download that manual but I'm working in the middle of nowhere Oregon so not sure if it will work with my phone. I appreciate all the advice, I'm more knowledgeable about my ride now. I'll post my final results when done. Cheers!

Tue Mar 17, 2015 2:25 pm

Shaunzo wrote: So ive got a new distributor ordered that comes with the hall unit. The screws holding the old one on are stripped bad so I just ordered the whole thing. The old unit has no broken wires but its pretty beat up so maybe thats it. My van should run nice after all these new parts haha. I'll download that manual but I'm working in the middle of nowhere Oregon so not sure if it will work with my phone. I appreciate all the advice, I'm more knowledgeable about my ride now. I'll post my final results when done. Cheers!

Did you test the Hall Sensor as outlined in the link I provided?
Or simply Guessing and tossing dollar bills at the problem?

Dave

Tue Mar 17, 2015 4:33 pm

The problem can be in the harness that attaches to the Hall sensor and not in the Hall itself.

Tue Mar 17, 2015 8:09 pm

And there are 10 other causes of no spark most of which cost very little money in parts to fix. Diagnose, test, repeat.

Mark

Tue Mar 17, 2015 9:22 pm

Well like I said I'm in the middle of nowhere Oregon so my options are limited since I only have basic tools. I tried to look thru the info in the link but it was a bitch to do on my phone. I'm also trying to get this work done while working 80 hour weeks so that makes it difficult as well. Throwing money at it IS dumb so I'll have to find WiFi somewhere and read thru that link on my kindle.

Tue Mar 17, 2015 9:50 pm

Makes me wonder what it was you had that you described as a brand new ignition control module :?:

Tue Mar 17, 2015 10:23 pm

delta9007 wrote: Makes me wonder what it was you had that you described as a brand new ignition control module :?:

Its an ignition control module for sure. The guy at the vw shop I went to knew what I was talking about and if you google it the pics show the exact part I have.

Anyways, I managed to get a good look at the link provided and I don't have a single one of the required tools for diagnosing the problem. I've given all my wires a good look over and can't find anything wrong with them although I won't rule out me missing something. At this point I think its either guesswork and replacing parts or put it in a shop. Both are going to be spendy. Buying a bunch of tools to diagnose it will be too. Its been a looooong time since I've felt this confused by a problem on a vehicle.

Tue Mar 17, 2015 10:28 pm

I guess I should make clear that Im no guru when it comes to cars but I'm far from ignorant either. Being away from home where I have access to tools and knowledgeable friends to help is just making this difficult.