Fuel Injection Help Please, 74 1.8 LJet Options

[SteveL]

OK - this all started a while back with the engine dying after running for a while and getting warm. Extensive troubleshooting followed.
Here is Where I am at:
New SMP Injectors and injector seals.
Connected HF fuel pressure gauge. Fuel pressure is good.
After installing new injectors, it ran good, until I broke one of the fuel injector connector wires while buttoning things back up.
Checked out the harness, and it is pretty questionable, even if I made the repair I could see. So, bought a rebuilt harness from Bowlsby.
Installed FI harness, and while I was in there, I replaced all vacuum lines, including the manifold connector hoses, and intake manifold gaskets.
All back together, now it cranks and gives 3 outcomes:
1: No start at all
2: Fires, runs for a cycle or two, then dies
3: Fires, revs up to about 3k, then dies (throttle action makes no difference)
I have rechecked all harness connections, they are solid. Rechecked vacuum lines, they LOOK correct, but we all know that if it looked right the first time, it will still look right the second time.

Help!!!! I am in MN and only have a few more weeks before the dreaded white crap falls from the sky and ends the season.

[SteveL]

Wonkipop - yep, I've been fighting issues for a while - but the target has been moving.
I have a backup dual relay that I will install in the morning...

[wonkipop]

Wonkipop - yep, I've been fighting issues for a while - but the target has been moving.
I have a backup dual relay that I will install in the morning...

i have a VW L Jet troubleshooting manual i found years ago on the net.
not saying this is your problem.
but it might be worth checking - just to tick it off methodically.
cold start injector.
given you checked and replaced all the other injectors.


the test is really simple as step 1. you pinch the fuel line into the injector. you leave everything in situ and unplug nothing. you crank and if it starts and runs then it is the CSinjector. i had to think about that and i'm guessing a leaky cold start injector causes the engine to flood? might be worth a try just to tick it off.

it does not sound like a vacuum leak, assuming you have all the hoses connected up correctly. i'm guessing you did the hose replacement methodically and have cross checked against the hose diagrams that are available (there are some up on this website). its a bit hard to do a vacuum leak test if you can't get the engine to run.
usually despite the talk of L jet being sensitive to vacuum leaks they will start and run, just poorly if there is a small leak.

ps - while these manuals are helpful, they don't necessarily cover all the bases 50 years down the track. for instance, while recommissioning mine, i could get it to start, but then it died. turned out it was running off a functioning CSinjector, but the other injectors were not opening. i'd had the injectors cleaned and tested, but in between testing and installing they had simply jammed shut again, too far gone with pintel corrosion from being laid up. no L jet manuals mentioned that in trouble shooting.
we knew the injectors were getting signal. i got hold of some new injectors and as soon as we installed them the car ran.