• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

UPDATE - she runs but leaks bad... Weird no-start '79 B21F KJet lamda

Verified spark at all 4 plugs. Disconnected the fuel pump relay, put a spare set of plugs on the ends of the wires, and watched them cycle while the key turned for a few seconds.
Installed a brand new fuel pump relay
Reinstalled my cheap Autozone coil to see if anything would happen
I verified timing again, I know I didn't do something like miss a keyway on a gear/etc because this car RAN with the gears installed this way. All three gears align with their marks.
I've tried jumping the blue wire direct to the coil, adding the brown wire from the starter, etc. Nothing.
Losing my mind here...
 
Bricktothefuture said:
Verified spark at all 4 plugs. Disconnected the fuel pump relay, put a spare set of plugs on the ends of the wires, and watched them cycle while the key turned for a few seconds.
Installed a brand new fuel pump relay
Reinstalled my cheap Autozone coil to see if anything would happen
I verified timing again, I know I didn't do something like miss a keyway on a gear/etc because this car RAN with the gears installed this way. All three gears align with their marks.
I've tried jumping the blue wire direct to the coil, adding the brown wire from the starter, etc. Nothing.
Losing my mind here...
Click to expand...

Why do all that after you verified spark
- I don’t want to know


Let’s start fresh
Air/fuel/spark to make it run

What’s your timing set to
Are you getting fuel out of injectors if you
Jump #5 and #7 fuse ?
 
Jack said:
Why do all that after you verified spark
- I don’t want to know


Let’s start fresh
Air/fuel/spark to make it run

What’s your timing set to
Are you getting fuel out of injectors if you
Jump #5 and #7 fuse ?
Click to expand...
At a certain point I start to hit the wall and just check whatever’s in front of me, even if it doesn’t make sense…

Cam gear at 0, factory position.
I’ve tried moving the distributor like 2-3 degrees through the whole range of motion and starting it - nothing.

I did the test with baby bottles and got good, even spray from all four injectors. Pumps kick in if I jump the fuses or move a were to a constant power breaker.
 
Jack said:
It’s a good tool to have
17 at harbor fake and about the same on Amazon

Hook it up start cranking while you’re moving distributor from left to right

Make sure to charge your battery
Click to expand...
I’ve been making sure it’s fully charged before each attempt. Two days of rain here in NH so it might be a bit before I can get back out.
 
I’m still concerned about the positive crankcase pressure and the backfires - I’m not sure this is pulling enough of a vacuum to lift the fuel metering plate. Anything there?
 
Bricktothefuture said:
I’m still concerned about the positive crankcase pressure and the backfires - I’m not sure this is pulling enough of a vacuum to lift the fuel metering plate. Anything there?
Click to expand...

If you’re getting fuel out of the injectors while cranking, it is pulling vacuum

Fuck man get the god damn starter switch then you can finger the plate while cracking it

Or get a gf or both. Someone or something needs to keep cranking it

Either way get your car running
Backfire would indicate fuel in the combustion chamber BUT wrong timing
 
Last edited:
jmiles said:
Does it have a cold start injector?
Does that spray when you try to start it?
Click to expand...
It should. BTW: this is what sidelined a friend's '78 245DL that had a B23E swapped in place of its B21F. One of the wires on the CSI harness connector had backed out. Reconnected it, and the car started up and ran, after sitting in his driveway for about 8 months with a no-start issue.
 
John242Ti said:
It should. BTW: this is what sidelined a friend's '78 245DL that had a B23E swapped in place of its B21F. One of the wires on the CSI harness connector had backed out. Reconnected it, and the car started up and ran, after sitting in his driveway for about 8 months with a no-start issue.
Click to expand...
This is a brand new Dave Barton harness, and the car did indeed run for a little while. I did have one funky pin on the ICU connector before that first successful start, but I reset that and everything looks good.
 
I'm wondering if something could've shorted out and maybe melted a wire during the time you did have it running. You say you have tested everything for continuity etc, but have you really inspected all of your wiring going through the firewall? Can you take a really close look at all of the wires that are related to your ignition system going from your fuse panel + ignition switch up through the firewall? Check the connections on both ends and everything in the middle. Check grounds.
 
Bricktothefuture said:
I know it’s spring because if I pull the intake tube some gas drips out. I’ve also tried starting it with that disconnected in case it’s too much.
Click to expand...

EDIT —————
I reread the thread and likely electrical - maybe it is that cold start injector.
The rest of my post could be crap
EDIT —————


This guy had a hard time with his KJet Audi -
at 15:55 in the video he gets into the funkiness of the cold start injector.
It may be that video or another in his series where he pull the cold start injector and puts it in a container to see how much is spraying.

Another thing the dude tried as a test was placing something in the air meter to hold it open a bit while starting. This would ensure the injectors have pressure and are firing at a rate higher than the idle level.

I point most KJet posts to Grey Goose Restorations channel as it has been very helpful to me https://youtube.com/@greygooserestorations?si=n2C10HIcVeeNTHPz

You have spark, so now it is a question of how much fuel it’s getting at start up time.
Something keeps me thinking that it is about that cold start injector.
So either running the startup with the cold start in a jar to see if it is spraying lots, or holding the air meter flap open a bit so that the main injectors are pressurized and spraying which should let it start without the cold start injector
 
Last edited:
You must log in or register to reply here.
Back
Top