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Sat Apr 03, 2010 4:07 pm

I've got a 1990 Vanagon with the 2.1L WBX. It was running great until a few weeks ago when it refused to start. I left it alone over night and the next day it started and ran fine again. Since then this has happened a few times and now it just plain dies while running and won't restart. I'm thinking it has something to do with the ignition but I don't know where to start. I pulled a plug and it was pretty dirty and the gap was much larger than the .028 spec. Should I replace the distributor cap, plugs and wires as a start? Thanks

Sat Apr 03, 2010 8:16 pm

Fuel, compression, and spark- and you probably haven't lost compression. Two easy things to try- first, when you turn the key to the first click, do you hear the fuel pump run for a second or so? That's not optional, it must happen every time. Second, remove a spark plug, lay it on the head with the high-tension lead attached, and have someone crank the engine. A nice blue spark should be observed. It helps to do this in a darkened area.

One of these two is likely your gremlin.

Sat Apr 03, 2010 10:48 pm

hall sender

Sun Apr 04, 2010 10:50 am

Thanks for the pointers. The van died on me yesterday and wouldn't start all day. I let it sit over night and got it to start this morning. I listened for the fuel pump which hummed for about 2 seconds as you said it should. I drove it around the block. I then parked it and let it idle for a few minutes at which point it died again, but this time I got it to restart immediately. I think I'm going to start by taking the plugs out, clean them with sand paper and reset the gap to see if it helps. If so, then I'll replace the cap, plugs and wires. Do you think I'm following the right course of action?

Sun Apr 04, 2010 10:56 am

more detail?

it dies while running & then won't restart

- what happens when you turn the key for a restart?

- any pattern as to when it dies? rpm; motor warmed up or cold, etc.??

- does it ever die when running for say 10-15 minutes - i.e. before the motor warms up?

Sun Apr 04, 2010 10:59 am

You likely have something electrical wrong. You need to troubleshoot. I have begun to hear lately of coils getting hot and not sparking well, as an example. You could have a bad connection. I have had the little pins inside the connector at the dizzy fail and cause much grief (I bought that one cheap and it took a few hours to figure out.) You need to be sure your ignition switch is not flaky. Your fuel pump delivers well. And so on. Guessing does not usually help much.....

Sun Apr 04, 2010 11:03 am

Yes it does seem to die when the engine is warmed up. So far it has been hit or miss as to whether or not it will restart after it dies, and now that you mention it, it almost always will restart when the engine is cold. What does this mean? I don't really have any more details. The fuel pump does hum when I turn the key.

Sun Apr 04, 2010 11:13 am

Yeah, this becomes like 'Automotive Charades.' Big box, three words; 'runs then dies.' We all shout responses and drink beer.

During this petit morte, does it have spark? You know, pull a lead and hold it close to the case and see if it will jump a quarter of an inch, or for a more dramatic effect, through your body, causing you to jerk spasmodically like Julius Caesar on a epileptic morning.

Does it have fuel delivery. Pull a bank of injectors and check the spray pattern like the manual says.

Check the fuel pressure, too high, too low. Both are undesirable.

Do you know what voltage your vehicle is making, like 13.2 VDC during this death, or 9.6 VDC, you may be running out of electricity as your alternator has given up the ghost and your battery is dropping down to unusable low voltage.

So many possibilities, download the ProTraining Manuals or buy a Bentley, trouble shoot a bit and report back. Meanwhile, we will suggest random things to you to check. Like did Oswald have a partner on the grassy knoll, did the Knights Templar have a hand in designing the WBX engine?

No fun, kids too old for eggs, makes me irritable.

Sun Apr 04, 2010 11:14 am

To answer your question directly, this has nothing to do with spark plug gap, ignition wires, or distributor cap.

What you have is probably an intermittent electrical problem in the fuel injection or fuel delivery system.

One not-very-scientific approach to sleuthing this out is to let the engine idle, then go around the engine compartment and gently move the wires around. If the engine dies, you're getting close. Same thing with the fuel pump wires, and the ignition switch. Don't forget the ECU plug, either.

Like I said, not scientific...but if it works...

Sun Apr 04, 2010 12:11 pm

Strike one up for the non-scientific approach! After reading your message I gently giggled the wires coming off the coil terminals. The engine died. I tried to restart and listened for the fuel pump hum. It did not hum, and the engine would not start. I went back to the coil and looked closer to find that one of the wires had come completely loose from the connector where I giggled it. I reconnected it securely and got it to restart! So thanks for your help! I owe you a beer.

Tue Apr 06, 2010 9:25 pm

oh man, jero, don't sand your points! replace them if you don't like them visually. that's middle-of-the-desert technology.
we all know what one of the things ben would say is....for 5 bucks , replace the ignition switch and eliminate a ton of mystery.
when you twist the key, does it turn but not fire?
my 90 would drive 3 feet in first and die. felt electrical. I unplugged the o2 sensor and replaced the maf capacitor, but couldnt get it to fail again in the following week , just before I put it in bitchen's 88. he's got hot wires on his speedo that shock him and other cluster problems [he bought a basket case] so I don't know if that was a lasting fix. it doesnt quit on him, but his temp lite blinks chronically. another capacitor...

when you start suspecting the ignitor, clean your throttle body-it drives the ecu crazy when it is coked up. you could then switch ignitors to see, just make sure it's the same kind. clean your grounds too. cheap easy items to narrow your search.

todd

Tue Apr 13, 2010 7:38 pm

OK, so I thought I had this thing figured out with the loose wire coming off the coil and all. Turns out that was just part of the problem (i.e. poor connections). The ignition gremlin is still rearing his ugly head though. The engine started just fine this morning but died once the engine had thoroughly warmed up. I removed a spark plug and tested but had no spark. I have a copy of Bentley's repair manual which tells you how to test the ignition components. I checked the hall sender for proper voltage and it was good. I disconnected all the wires from the coil and removed the coil from the engine bay. The terminals were a mess. I cleaned them up as best I could and tested the resistance on the coil. The manual says that I should get a reading between 0.5-0.8 OHMS but I got a reading of 1.5 so I'm outside the acceptable range. I reconnected everything and tried starting the engine. It started. I let it warm up and it died again.

I assume the coil will operate outside its given parameters of 0.5-0.8 but my question is this: could the heat from the engine be pushing the coil past its operable parameters? And with the troubleshooting I've done is it worth taking a $90 bet to replace the coil?

Thanks for your help

Tue Apr 13, 2010 9:31 pm

It could be the coil, replacing original ones is just good practice by this age anyway, and you do have the primary at a low value which means low power. If your high-tension stuff (coil, cap and rotor, plug wires, plugs) is old or of questionable age or quality then by all means replace it all. No engine will run well for long if the HT circuits are marginal.

But the amount of time the engine is running before cutting out doesn't seem long enough to warm up the coil much. Do you think that each time it has started the engine itself has been fairly cool, and when it does start does it run about the same amount of time if it just idles, or less if you drive it, before it dies each time? if so, I would put in a new Temp2 (coolant temp) sensor.

Fri Apr 16, 2010 12:59 pm

Ok so I'm still at a loss on this ignition thing. At this point I have replaced the ignition coil, the cap and rotor, and plugs and wires. All with the proper Bosch parts. As soon as I had these things replaced I test started the engine. It roared to life for about 5 seconds and then promptly died again. I have not been able to get it to start since then. The engine just cranks but doesn't start. I checked to see if it has a spark and it has none. I've also checked to make sure I'm getting fuel to the engine which I am. I've tested the hall sender unit and am beginning to suspect it is no good because when I test the three wires coming out of the halls connector plug on the distributor, one at a time during an engine test start, none of them give me a flicker on my voltage tester like my Bentley manual says it should. Any info I can get from you Vanagon Gurus out there is surely appretiated. I'm not much of a mechanic but I'm tryin to learn. So should I replace the halls unit in the distributor? And is this a "difficult" task? What should I be aware of before I take this stuff apart and put it back together? The Bentley manual has good diagrams but it doesn't really tell you what to watch out for. Thanks

Fri Apr 16, 2010 1:34 pm

What you need to do is figure out if it is wire or electronics. If the hall gives no signal, you will get no spark. There are a few things that go wrong. Due to the heat from the block, the three wires tend to get brittle and crack. The connector also suffers this heat and age and cracks. The pins in the connector can push out and make poor contact (look inside the connector and see if they are pushed back at all). The connector on the side of the distributor cracks and the connections short out to the body of the distributor.

So as a first step, take your meter and see if the signals are good to the connector on the ECU. Move things a bit to see if the interrupt. IF your not getting power out there it is a god place to start.

Fri Apr 16, 2010 8:01 pm

Yeah, my hall sender must be no bueno cause I've got no spark, my temp 2 and air flow potentiometer are OHMing out OK, I've replaced all the high-tension stuff, and I'm pretty sure I have continuity between all my connections. I've thoroughly inspected the connectors and pins on the hall sender, as Dogpilot mentioned above, and they appear to be good. . .

So I went ahead and pulled the distributor shaft apart from the engine leaving the distributor crankshaft in place. This is where I hit my next problem. I'm having a hard time getting the pin at the bottom that holds the shaft in place out so I can pull out the shaft and get to the actual hall sender itself, and replace it. Do I need to get it pressed out at a mechanic's shop or something, and then when I reassemble it, will I have to get the new pin pressed back in?

Sat Apr 17, 2010 9:04 am

jeroland wrote: Do I need to get it pressed out at a mechanic's shop or something, and then when I reassemble it, will I have to get the new pin pressed back in?
I hope someone jumps in on this, because I have been wondering the same thing. I had a sacrificial dizzy that I tried to remove the pin from and I couldn't get it to budge and I really whanged it good with a stout nail and hammer.

Sat Apr 17, 2010 10:27 am

So when it won't start, it turns over but you don't get the fuel pump hum or spark? Are you getting 12V at the coil + terminal when it doesn't start and key is in the on position? Were any fusse popped at any point? Shiny insulation/melting wires?

Tue Apr 20, 2010 9:55 am

deprivation wrote: jeroland wrote: Do I need to get it pressed out at a mechanic's shop or something, and then when I reassemble it, will I have to get the new pin pressed back in?
I hope someone jumps in on this, because I have been wondering the same thing. I had a sacrificial dizzy that I tried to remove the pin from and I couldn't get it to budge and I really whanged it good with a stout nail and hammer.

OK, I have a bit more info on this. I took the dizzy to get the pin removed at my local VW mechanic but he wouldn't touch it. He said I was better off just buying a new one because the risk of damaging the shaft is too great in trying to remove the pin and rebuild the distributor. It would have been about $120 to put in a new hall sender alone. Now its costing me $330 on Van-cafe for a rebuilt distributor and I'll get $100 back for the core. I guess that's the best way to go. . . Just trying to save a buck, and learn some stuff in the process, by doing this stuff myself. I really hope she starts when I get this stuff all put back together. . .

Tue Apr 20, 2010 3:00 pm

jeroland wrote: He said I was better off just buying a new one because the risk of damaging the shaft is too great in trying to remove the pin and rebuild the distributor.
Well that is definitely total, utter bullshit. People replace hall senders all the time on these things.