Cranks spark and fuel yes no start next steps?

[mikemtnbike]

Yesterday, I'm about 400 miles into driving my van after waterjacket seal replacement, new cylinder sleeve o-rings, new coolant hoses, new exhaust, lots of little things like cleaning grounds and new motor mounts and more. Full V-C tune up kit installed. I've never done anything this big before, so I did pay a pro to look my work over, including timing, valve adjustment, etc.

Leaving a campground that included a couple of creek crossings, van starts to fall on it's face. Stumbling as I give it gas, stalls out. Automatic. Starts right back up a couple of times, seems like it's going to run, but then stumbles and stalls. Inch forward to a better parking area, curse a lot. Starts and stalls a few times, when it stalls I can hear a hard close coming from the intake air flap. Then it won't start back up and it's acting weird; it cranks, seems like it's going to catch, the starter disengages, but then it doesn't start and the starter kicks back on. Think I might be out of gas, put some in, nope. Work on it some, catch a ride home, take today off work and get it towed home.

Here's what I know:

- Initially, I was only getting drips from the fuel pressure T when released after cranking- I had high hopes... I changed the fuel filter with a spare. There was no water in what came out of the old filter (creek crossings remember?). I have strong flow now from the T when released and the driver side injectors spray an intermittent cone-shaped mist when cranking. I have not actually measured fuel pressure yet. I did put 1/2 a bottle of red Heet in too.
- I have spark from #3 plug and from coil. All plug wires are on and plugs are snug and clean looking when taken out. The wires are connected to the distributor in the correct order.
- The temp II sensor checks good.
- TPS seems adjusted right and is measuring at 5 volts.
- Rotor still lines up with TDC mark for #1. The dizzy was not wet.
- ICV hums.
- Fuel pump primes and hums.
- Doing the intake air sensor checks from the Bentley, I have the right resistances between 3 & 4 and 1 & 4. I cannot get any measurable change in resistance between 2&3 by moving the air flap. I have no idea what this test means, but it's not in spec, but I might not be doing it right. Being honest here...
- Trying to start it with the whole air intake housing off is probably a bad idea, but I can tell you it makes no difference. This is with the plug attached to the AFM or intake air sensor or whatever it's called both plugged in and unplugged.
- The starter is staying engaged as it cranks but doesn't quite catch now. You can hear it ALMOST starting, but then it doesn't, but the starter keeps chugging. I did hook the battery up to a jump start pack and it's checking at full charge at this point.
-There are no loose wires coming off the starter.
- Shudder..there is no milkshake in the oil or coolant, I did check.


My next steps were going to be:
Check #1 plug for spark.
Check injectors on that side too.
Start pin testing per Bentley 24.61-2
Get it towed to the shop.
In about that order.
Is there anything obvious I'm missing or should try next?

Going to a friend's house for Halloween beers around a fire, so not going to check this for a few hours. Appreciate any help or thoughts, including telling me exactly what stupid thing I've done or am missing...I'm a grown up.

Thanks!
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1991 Vanagon GL 2.1 AT Westfauxlia. "Frankie" Totaled https://www.thesamba.com/vw/forum/viewtopic.php?t=764510&highlight=carnage
1995 Eurovan Camper "Marzivan"
2020 GTI SE manual

[mikemtnbike]

I decided to take my own advice and get it towed to the pro, doing so tomorrow morning.
This same vanagon specialist mechanic (I'm lucky to live where such things exist) recently fixed two broken wires to my ECU and he's thinking maybe I've got more wiring harness issues going on, maybe even the main cable to the starter or the alt wiring harness. Or a ground even though I've checked all those. So, rather than throwing parts at the problem, going to see if spending money for knowledge works out.
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1991 Vanagon GL 2.1 AT Westfauxlia. "Frankie" Totaled https://www.thesamba.com/vw/forum/viewtopic.php?t=764510&highlight=carnage
1995 Eurovan Camper "Marzivan"
2020 GTI SE manual

[Wildthings]

Have you removed the distributor cap and checked for moisture?

[mikemtnbike]

Yes, it's like 4 or 5 in my overly long list above of things I'd done.
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1991 Vanagon GL 2.1 AT Westfauxlia. "Frankie" Totaled https://www.thesamba.com/vw/forum/viewtopic.php?t=764510&highlight=carnage
1995 Eurovan Camper "Marzivan"
2020 GTI SE manual

[Tom Powell]

I have a spare ECU that is known to be good. I would swap in that ECU because it's easy to do. I also have the VC digitool and I would hook that up and check the readings as it cranks. I would also mist the engine with water on a dark night and look for dancing gremlins. Ignition switches are also a usual suspect for no start and intermittent poor running.

Aloha
tp

[Vanhalla]

Check the connector behind the distributor is clean ( I think it's the hall connector) and making good contact.
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1991 VW Vanagon GL

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