1980 Vanagon Camper Dies Randomly

[vol.ff4312]

I got this from my dad a few months ago and have a nagging problem where the bus will start fine, drive a mile or two and then want to cut out. I've had it happen while idling at a light and while driving 35mph. Cruising as well as accelerating. I've had some success with backing off the gas pedal while in motion and can coax it back to life but not always. When it dies I can usually pull over and restart. I've replaced the fuel pump, filter and temp II sensor with no real change in symptoms. I tested for vacuum leaks today with starter fluid and had no reaction. Did a vacuum test and its pulling roughly 11 inches (seems low). Tried moving bits of the harness around while running and no dice. Took ohm readings from the AFM and all were within spec. It is California emissions so not sure what monkeys are throwing in wrenches with that being the case. I plan on doing some more pin and voltage checks when I get home from work tomorrow but something tells me that they will probably be within spec due to the Jekyll and Hyde nature of the problem. Motor was rebuilt a few years back and has less than 2000 miles on it so I'm going with electrical or fuel delivery issue.

-Is it possible to suck air from the gas tank, the pump seems awfully loud for being new even on a full tank?

-Could the signal from the ECU to the injectors be dropping out?
Seems like if I lost spark the engine would die immediately like the ignition was switched off. This doesn't act like that. Its like a stutter that I can sometimes recover from by backing off the gas. Which makes me think the injectors aren't firing right. Or the fuel regulator is having a fit.

-Once warm there seems to be a real slight hunting for idle. Maybe 50-100 rpm difference and the cycle back and forth is extremely slow.

Just trying to get some ideas. My prior experience to this is with carburated super beetles and a 76 mini. Not used to this injected stuff!

[a1fa]

Surging idle is usually an air intrusion past AFM. It could come from anywhere, including the brake booster, throttle body, deaccelerator valve, any of the rubber... but since you have California van, it has idle stabilizer that could be messing with you too.
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Learn to ride. Ride to learn.

[reluctantartist]

If your van has the original jet with oxygen sensor I think the vacuum reading my be right. Depending on how you are doing it. I would check your electrical connections at the starter , at the battery,ignition coil,fuel pump, and maybe the atm. I had a similar situation and it was because I wax forgotten to tighten the wire to the starter when I replaced it.
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1982 Westy, 1974 412 Variant... Yes, Aircooled's are great! Oh and I do have modern computer controlled vehicles too, but I just don't care about them.

[Steve M.]

The only way to do this for sure is to start out by following the steps to check the Fuel Injection System as noted in the Digifant Pro Training Manual or the Bentley.
These are known parameters that you can measure.
Once you "know" for certain the are good then you can stop guessing about them.

Do a search for that and download it. It on the internet somewhere for free.
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This free advice is worth exactly what you paid for it.

There are seven days in a week. Someday is not one of them.

[Navy_Flyer]

Your symptoms sound very similar to my experience a few months ago - starts and runs fine, then stops suddenly. Wait a few minutes, re-starts fine, rinse and repeat.

Turned out to be a bad battery - check the health of your battery under load.
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1987 Westfalia, Automatic. EJ25 VANARU Conversion

[bokonon42]

Mine did this as well- even after getting a new alternator and battery, but went away after Van Cafe installed a new Alternator cable. http://www.van-cafe.com/alternator-cable-upgrade My battery was just not getting enough juice from the alternator apparently.
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Terry
88 Vanagon Wolfsburg Carat - https://www.thesamba.com/vw/forum/viewtopic.php?t=671319

[MarkWard]

When these vans were new under warranty, they'd do something similar, but more like it would fall on its face just going down the highway and run fine again. One of the recommended fixes was to run a dedicated ground wire from the battery negative terminal to the engine case. VW suspected a ground issue even back then. Short of running a dedicated ground to the case, I would take all your engine harness grounds off and clean them with some scotchbrite and reattach. Grounds are often overlooked.
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☮️

[vol.ff4312]

Thanks for the suggestions guys. It defiantly "feels" like some sort of electrical or signaling issue. Load testing the battery, cleaning grounds and the Van Cafe fix make sense. I've seen low voltage conditions wreak havoc and create dashboard Christmas trees with newer cars. This bus does typically sit for long periods. Once and awhile I have to use a booster to get it started. I'll try and get a voltage reading tomorrow when I get home from the alternator and the battery location to see if that can tell us anything. At what voltage drop does the battery light come on? I usually have to blip the throttle to get the oil and battery lights to go off.

[E1]

Note that the ECU does not affect operating condition for roughly one to two minutes after firing.

Once the computer sends signals for fuel mixture, ancillaries like the O2 sensor and the Temp II sensor are engaged, and if either has gone South the running condition is pretty similar to what you describe.

What you could try to eliminate this as your issue:
1). Start the van, rev to confirm it revs well;
2). Check a spark plug;
3). Re-start and drive around to confirm it's a horrid mess;
4). Recheck same plug.

Good Luck!


Edit: Know this method is good for a Wasserboxer.

I know less than nothing about the 2-liter air-cooled… so if the above advice is crap, send a PM for a photo of myself to use as a dart board.
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‘84 Westy, 2.1L with Digijet, 5.43 R+P, GT Gears
"Adding power makes you faster on the straights.
Subtracting weight makes you faster everywhere."
— Colin Chapman

[vol.ff4312]

Hmmm.
I replaced the temp 2 sensor with a supposed good unit and still have the issue.
Maybe the O2 sensor is kaputt? It doesn't take long. Maybe 5 minutes before it starts acting up but only once underway. I can idle in the driveway for quite a while and even rev it up without it cutting out but once on the road and after a couple of throttle changes its a different story.

[Stuartzickefoose]

Have you got a picture of your engine by chance? I had an issue with my 80 that’s similar but want to see a pic of your FI first.
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Stuart Zickefoose

2011 Jetta Sportwagen TDi 6 speed manual

206-841-7324
[email protected]

[vol.ff4312]

Sorry for the poor quality but its pitch black out back right now.

[Stuartzickefoose]

Here’s what I was curious about:

https://www.thesamba.com/vw/forum/viewtopic.php?p=7551134#7551134

Wiggling it would kill the engine at idle, so an easy check if you’ve got this. Ties into the coil power somehow if I remember right.
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Stuart Zickefoose

2011 Jetta Sportwagen TDi 6 speed manual

206-841-7324
[email protected]

[vol.ff4312]

Is that the Temp II connection?
There is already some odd stuff going on here in my engine compartment. There are 3 newer green plastic covered spade connections and a random green wire with a splice connector. This thing did have an aftermarket cruise control that I removed the servo and vacuum lines back here to help rule that out. Haven't done anything with the control unit up front yet though...
The 3 aftermarket connectors are all grouped with the white wire bundle going to the double relay and the splice runs off of a wire running inside the harness to the component mounted on the heat sink made by Fairchild (what is IT? The Idle stabilizer? I can't tell from the Bentley. Looks like I may be missing something?)

[Stuartzickefoose]

No not the TS2. That’s a single usually black wire going to a 13mm nut on the left head there.

I would suggest with engine running if you suspect a wire over there, wiggle them fairly vigorously and see if the engine misses. Ideally if you can duplicate the problem consistantly then we can pinpoint the issue easier.

Other two things I would check are the air flaps, the throttle body and the AFM, and see if they stick at all in their swings. Test the throttle body by twisting it by hand with everything off (like key off engine off, don’t have to take the cable etc off) to full throttle, shouldn’t stick at all. The AFM, if the black plastic cover is not glued down you can move it with your finger gentle on the electronic side to test the same swing, no sticking. If the cover is glued down still, leave it alone, and gentle press it open fully with the butt if a screwdriver handle and test the full swing.
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Stuart Zickefoose

2011 Jetta Sportwagen TDi 6 speed manual

206-841-7324
[email protected]

[danfromsyr]

just a note to add once you get this running and driving properly.
you are missing the cooling flaps and thermostat on your motor.

you'll want to make sure the oil cooler is getting sufficient airflow with the flaps missing.
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[RicoS]

[kaalualu]

Could be those mice gnawing on wiring, you can see their "signs" on that ledge. Vehicle sitting unused by humans, can become home for rodents.
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'84 Transporter 16" CLK's/LED's/ AT's/Mansi injectors
'86 Wolfey Weekender Westfalia AT's/otherwise stock
Sold-'82 TinTop Diesel

[vol.ff4312]

@ Dan, What exactly does a setup w/ flaps look like? Forgive me I'm still learning the anatomy of this bus. Is that the rod looking thing with a spring that runs East-West just aft of the distributor cap in other photos I see?

[vol.ff4312]

I definitely think there is some sort of vacuum leak going on here at a minimum. I can hear a hiss up near the throttle body area at the head of what I call the "spider" aka intake manifold. I tried using starter fluid to isolate a leak but no matter where I spray there is no change in engine rpms. I took apart the intake down to the plenum body. Couldn't find any cracks in the boot but the seal between the TB and the plenum seems sort of hard and had some oil ringing it. Oil appears to be coming from the crankcase breather. Boot is also hard and bottom seemed swelled from having oil in the bottom. How much oil in the intake is normal?

On another note I did some experiments with the full throttle switch as I gather they can cause some issues as well. Switch has continuity when depressed but no effect on the engine at least while at idle. There also seems to be less than half a volt measured between the two wires. Not sure if that means anything.

Another observation is when I disconnect the O2 sensor the engine seems to hunt around less but it takes longer to settle down into an idle when I blip the throttle. Again not sure if it means anything just reporting what I observe.

third observation is when I had the intake apart there is a sensor mounted on the case up by the flywheel under the TB that has had the wire snipped off of it. I didn't see from the harness where it would connect too. Looks like a speed sensor of some sort but I'm not sure.
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Shane N.

1974 Super Beetle
1980 Vanagon Westy
1976 Leyland Mini


All as stock as I can make them!