Fuel injection help please (air-cooled)?

[Vivavanagon]

Just picked up a 1981 Vanagon manual trans 2.0l

Had not ran since 2011,
Replaced starter , battery ,fuel pump and filter and added fresh fuel
The van will start and run on carb spray so I know the ignition system is working my concern now is I have no fuel injector pulse and also the fuel pump does not run momentarily when key is turned on,pump will run when I move the arm in the airflow sensor.
Reading schematic I see I need power to ecu on pin 10 and trigger for injectors on pin 1
My first question is ground at really pin 85 I see in the diagram it goes to the ecu and have seen some here that ground goes right to the body at the relay , I am trying to verify power to the ecu but it seems if I disconnect the ecu I loose the ground thus no power to pin 10 ?
Any advice going forward greatly appreciated !
I am a 30 year senior master tech for Ford so I have a pretty good understanding of fuel injection and electronics

[brickster]

Welcome! From the Vanagon Essentials ~ The FAQ Guide sticky topic at the top, you will want to download the Digijet ProTraining Manual (first link is dead, but second one is alive).

There is a functional wiring diagram as well as test procedures for the entire system.

Once you get it running, replace your fuel lines. Then, I would recommend cleaning and improving the ground system. I found that many of my FI sensor readings were off until I cleaned them all up and added auxiliary grounding between the starter and body.

Since it's been sitting for a long time, carefully inspect for signs of rodent damage.

[hdenter]

I'd double check that the early air cooled are on Digijet. '83.5-'85 are, but the air cooled may be different. Air cooled have the cold start injector and some other things that water cooled don't have....

Hans
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'79 triple white convertible bug
'84 sunroof vanagon
'85 weekender

[Wildthings]

Injectors can stick shut from sitting. I got hold of a Toyota V6 pickup that had been sitting for 10ish years and was getting no fuel through the injectors, but it would fire on starting fluid. I added FI cleaner to the fuel and messed with it for quite a while without getting a start. Went inside to let the battery charge and peruses the manual a bit and came back out a half hour later and hit the key. I got a single hit out of one of the cylinders and thought is was just a tad of left over starting fluid, but it hit again a single time after maybe 10 seconds of cranking time and I knew that I had won. Alternated giving the starter a rest and cranking and within a minute of cranking time one cylinder was hitting repeatedly and then after maybe two minutes of total cranking time a second cylinder had kicked in and it was nearly running on its own. Another minute or so gave another cylinder so no more cranking and by another couple of minutes the engine was sitting there purring like there had never been a problem to begin with.

A lot of people claim injection cleaner is snake oil, but any more its my go to whenever an engine is running a bit rough.

The fuel pump doesn't run when you just hit the key. Instead, it runs instantly when the starter is engage as a wire feeds from the extra set of contacts in the starter solenoid directly to the fuel pump relay.

[RawUmber]

[brickster]

[RawUmber]

[RawUmber]

[danfromsyr]

the air cooled fuel pump does NOT run when you first click of the key.
fuel pump will ONLY run when the starter is cranking & then once the AFM arm moves the contact points under the cover.
there SHOULD be a wire from the starter to the double relay, this is what tells the double relay to run the pump while cranking over.

you may likely NEED to pull the injectors and verify that they want to spray and that they have a nice pattern. you REALLY SHOULD remove and replace the seals under the injectors anyways.. a common source for a rough idle by allowing unmetered air in

for testing purposes you CAN provide the fuel pump directly with +12v and have it run, injectors shouldn't spray unless there's a signal from the AFM & coil (tach side)
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[Vivavanagon]

Thanks for all the info got her running tonight. A little smoky a little bit of a high idle but she’s running!
Just have to iron out a oil leak on the left side then new injector seals and fuel hoses .

[kamzcab86]

[Vivavanagon]

So went back at it today changed the oil and went to start her up and back to square one.
Cranks now like it has no compression and a random clacking noise while it cranks. Pulled plugs and all were fuel fouled. Gonna try with a set of plugs next and see if that helps. Still not surw what by he clacking noise is.

[brickster]