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  #16  
Old 04-15-2018, 09:01 AM
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Location: Cleveland, Ohio
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Here's the way I got the car.

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CIS K-Jet Help needed-warm-up-regulator-vacuum.jpg  
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  #17  
Old 04-16-2018, 07:48 PM
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Been a long time since I messed with it, but I think the aviation Form-a-gasket was the only one that was fuel proof. Unless you used that particular sealer, the sealer probably failed and caused the leak, not excessive pressure. If it was excessive pressure there would be fuel spraying everywhere.
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  #18  
Old 04-17-2018, 08:46 AM
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Thanks, but since I had a spare fuel distributor from a known good 450SLC I just swapped it, and will worry about the FD later.

I really don't think the fault is the k-jet. I'm starting to think that the only reason it has started is because the fuel pump is on during start. And doesn't stay on in "Run" So I'm gonna start by looking for the fuse and go from there.

Not sure about the vacuum going to the warmup regulator. And swapping them had no effect. So I'm confused, 1976 hooked up one way, 1979 hooked up the other possible way. Now, the 79 didn't really run all to well, so maybe I should put it back the way I found it, something my parents always told me to do. Anyone know which way it's supposed to be hooked up?

The attached schematic. When the switch is in Start position, the relay labeled A/C starter relay is energized. When this happens the fuel pump is getting 12v through the A/C starter relay (which I believe also disconnects the A/C compressor) But when the ignition switch is in "Run" position, if the fuse is blown, the car will start and stall after consuming the fuel from the cold start valve.
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CIS K-Jet Help needed-startupschematic450slcapture.png  
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  #19  
Old 04-17-2018, 09:03 AM
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Quote:
Originally Posted by mespe View Post
I'm starting to think that the only reason it has started is because the fuel pump is on during start. And doesn't stay on in "Run" So I'm gonna start by looking for the fuse and go from there.
See post #3, again. Unplug the safety switch.
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  #20  
Old 04-17-2018, 10:11 PM
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It's been unplugged. Someone messed with the wires and did a bit of sloppy splicing.

I decided to wait a day because of the cold weather and snow. I am working in a garage, but I didn't want to go out in the miserable weather.
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  #21  
Old 04-19-2018, 05:38 PM
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Digging further I discovered that the brown/white wire going to the Fuel Pump relay got fried and the insulation melted off. I couldn't figure out why the brown/white wire at the baffle switch was grounded all the time.

So For a test I cut the brown/white wire by the fuel pump relay, and tried the car.

Same thing, start, runs a few seconds and dies.
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  #22  
Old 04-19-2018, 06:57 PM
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Next troubleshooting step, I wired the fuel pump directly to the black/white/green wire (hot when ignition is in run) and same thing, runs a few seconds and dies. So the problem has got to be either mixture control, pressure regulator, air by-pass, or warmup regulator. It's supposed to warm up a little tomorrow, so I might swap those out.
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  #23  
Old 04-19-2018, 07:37 PM
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Quote:
Originally Posted by mespe View Post
Next troubleshooting step, I wired the fuel pump directly to the black/white/green wire (hot when ignition is in run) and same thing, runs a few seconds and dies. So the problem has got to be either mixture control, pressure regulator, air by-pass, or warmup regulator. It's supposed to warm up a little tomorrow, so I might swap those out.
Does the fuel pump actually run continuously when the key switch is in "run"?
If not, remove the pump relay and jumper the hot socket (87a/#2) to the pump socket (30/#3).
Once the pump is actually running continuously, then go thru the starting sequence.
It is possible that the engine is running only on the cold start injector.
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  #24  
Old 04-20-2018, 01:37 PM
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Originally Posted by Frank Reiner View Post
Does the fuel pump actually run continuously when the key switch is in "run"?
If not, remove the pump relay and jumper the hot socket (87a/#2) to the pump socket (30/#3).
Once the pump is actually running continuously, then go thru the starting sequence.
It is possible that the engine is running only on the cold start injector.
Pump runs continuously.

That is exactly what I did, and got same results. Yes I agree, car is only running on cold start injector.

I pulled the mixture control unit today, as I have a replacement (along with pressure regulator and warm up regulator. I noticed some melted vacuum lines and all the rubber connections are hard and loose. So before I go any further, gonna replace all the rubber vacuum parts and the melted line. Will also inspect for other vacuum leaks since the mixture control unit is off.

Currently the fuel pump relay connection 85 has no wire going to it (Brown/white stripe) it got so hot that the insulation melted away inside the fuse box. That same wire outside the fuse box looks ok, but is very hard.
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  #25  
Old 04-20-2018, 03:29 PM
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Originally Posted by mespe View Post
I pulled the mixture control unit today, as I have a replacement (along with pressure regulator and warm up regulator.
You probably realize this, but the fuel pressure regulator is not a separate device. Fuel pressure is regulated inside the fuel distributor (FD).
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  #26  
Old 04-20-2018, 06:49 PM
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Quote:
Originally Posted by Frank Reiner View Post
You probably realize this, but the fuel pressure regulator is not a separate device. Fuel pressure is regulated inside the fuel distributor (FD).
The pressure regulator that is connected to the warm up regulator and the FD.

Chanced up this
http://www.taunusfinland.com/tiedostot/ford/K-Jetronic/K-Jetronic-schema+troubleshoot.jpg

hard to read that jpeg, but it say for when starts and immediately dies,, fuel pump, excessive fuel delivery, warm pressure to hi/lo, or primary system pressure out of tolerance.

So by replacing the FD, mixture control unit, warm up regulator, pressure regulator, the only other parts suspect parts should be fuel pump and accumulator (and for those I gotta crawl under the car.)

But for now, I must wait to get some vacuum lines. Went to a VW dealership and he told me all their lines are custom made. Oriely's wanted $6 for about a foot of the plastic vac line, I need about 2 meters,,, so when I get to my shop, I scrounge some up.

It sure got hot in there, as a couple vacuum lines actually melted.
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  #27  
Old 04-20-2018, 07:49 PM
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Quote:
Originally Posted by mespe View Post
The pressure regulator that is connected to the warm up regulator and the FD.

Chanced up this
http://www.taunusfinland.com/tiedostot/ford/K-Jetronic/K-Jetronic-schema+troubleshoot.jpg

The fuel pressure regulator, item #5 in the schematic, is actually inside the FD.
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  #28  
Old 04-20-2018, 10:34 PM
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this thing

whatever this thing is,,,
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CIS K-Jet Help needed-part.jpg  
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  #29  
Old 04-20-2018, 11:07 PM
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Originally Posted by mespe View Post
whatever this thing is,,,
Is that in the line that runs from the top center of the FD to the control pressure regulator (WUR)?

If not, what is connected to it?
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  #30  
Old 04-20-2018, 11:25 PM
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Join Date: Nov 2014
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That last part is a fuel pressure damper.

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