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76 K jet 240 died @ red light + now wont start..

Radtap said:
They should be anytime you open that connection, they're supposed to be copper crush washers and will create the seal as you crush them with the banjo bolt. Pick up a pack of assorted sizes from a local auto parts store, K-jet cars have a lot of them in the fuel system. I broke a banjo bolt off in a fuel dizzy stubbornly trying to make an old crush washer seal instead of replacing it.
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ebay a metric set of copper washers for you kjet needs
 
tibboy12 said:
You and I have similar issues with our cars.. I recently had my fuel dist rebuilt but still kept experiencing problems so I just dropped my car off at a shop here in Portland. They found that my car was running super lean, so I’m hoping when I pick it up tomorrow all the fuel related issues I’ve had are gone. Fingers crossed… 🤞🏽 you got this
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Did your shop solve this?
 
302ftw? said:
Did your shop solve this?
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They said my car was running very lean, and that my fuel mixture screw was very much stuck. They adjusted it and so far, the car has always started warm and cold. I did notice that they took off the resistor near the coil, and when I plugged it back in my car would not start at all just crank and when I took it off car started right up. Going to drive it more this weekend and see how it does.

I’m also noticing that my main fuel pump is louder than normal so I’m going to diag that too.
 
tibboy12 said:
They said my car was running very lean, and that my fuel mixture screw was very much stuck. They adjusted it and so far, the car has always started warm and cold. I did notice that they took off the resistor near the coil, and when I plugged it back in my car would not start at all just crank and when I took it off car started right up. Going to drive it more this weekend and see how it does.

I’m also noticing that my main fuel pump is louder than normal so I’m going to diag that too.
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What's the resistor near the coil?

I took my car on its longest ride since "fixing" my most recent issue. After shutting it off at my destination it would not start back up. The whole ride it was smooth, idled well at stops etc. Im going to check + maybe pull the alternator later today. I have a denso 100 amp I can swap in. Im thinking the extra heat from the kl headers has baked my 55 amp bosch alternator. The voltage has been kind of sporadic - between 11.5 - 14
I have the ci injection fault tracing green book, I'll bring that with me and start doing all the recommended voltage tests also.
 
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rearwheelpeel said:
What's the resistor near the coil?
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The resistor near the coil drops the coil voltage when running. When cranking, the coil is fed the full +12v from the starter. If you download the '77 greenbook TP12045 from ozvolvo.org/archive/, you can see the resistor on pg 16 (starter circuit) and pg 18 (ignition circuit).

When it's misbehaving, measure the voltage on the coil + (or 15) tab with key on and make sure it's not zero. (It'll probably be 12volts, but might be a bit less due to breakerless ignition behavior.)
 
rearwheelpeel said:
What's the resistor near the coil?

I took my car on its longest ride since "fixing" my most recent issue. After shutting it off at my destination it would not start back up. The whole ride it was smooth, idled well at stops etc. Im going to check + maybe pull the alternator later today. I have a denso 100 amp I can swap in. Im thinking the extra heat from the kl headers has baked my 55 amp bosch alternator. The voltage has been kind of sporadic - between 11.5 - 14
I have the ci injection fault tracing green book, I'll bring that with me and start doing all the recommended voltage tests also.
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IMG-1145.jpg

This is what it looks like on mine. I think yours is inside your fender well or something if I remember right from previous posts.
 
Yeah the resistor on my car is mounted behind the grill area. I got it started back up again and drove it back home. It runs great and drives beautifully when it is running. I think I actually caused this issue myself when I recently installed my radio. I have been doing so much rewiring and replacing old wires behind the dash that I've kind of lost track of whats what. I should've been really labeling things better. So my radio I believe** has been draining the battery enough that when I do drive it far enough it doesn't have enough juice left to start the car again. The digital voltage gauge on my dash has been very helpful as I can monitor the voltage more precisely than the needle gauge. Im going to replace the alternator to starter wire and ground later just because I haven't yet. But I can confirm the alternator is still charging the battery.
 
I do have another question - when I was cleaning up the fuel pump(s) wiring in the trunk I disconnected the 2 wires from the plastic connector that the *radio interference relay?* plugs into. Its a black plastic 2 prong connector, one ground one power. I plugged them back on but am not 100% sure I put them back in the right spot. If these were NOT plugged in correctly, would the car still run?
When I still had the radio plugged in after doing the trunk wires, I noticed the graphic equalizer was moving a little bit even with no music playing from the speakers....

Edit** 240s dont have a radio suppression relay i guess. What is this little black rectangle in the trunk?
20250914_100723_copy_3754x2815.jpg
20250914_100704_copy_2852x3802.jpg
 
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rearwheelpeel said:
I do have another question - when I was cleaning up the fuel pump(s) wiring in the trunk I disconnected the 2 wires from the plastic connector that the *radio interference relay?* plugs into. Its a black plastic 2 prong connector, one ground one power. I plugged them back on but am not 100% sure I put them back in the right spot. If these were NOT plugged in correctly, would the car still run?
When I still had the radio plugged in after doing the trunk wires, I noticed the graphic equalizer was moving a little bit even with no music playing from the speakers....

Edit** 240s dont have a radio suppression relay i guess. What is this little black rectangle in the trunk?
View attachment 34433
View attachment 34434
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What’s all wrapped up in the black tape?
 
I am still fighting with this car. Something is draining the battery overnight. I replaced the alternator with the spare denso 100 amp I had and it charges great although im going to have to pull it out again to replace the bearing because it's loud as hell. I have replaced 99% of the wiring in this car. It has the original bw55 trans. When I have the battery fully charged, the car will start like it always has. When I put it into drive the voltage drops from 14 to 13, and starts jumping around from 13.2-13.6... etc etc. and the idle surges. Shift it back to park and the voltage goes back to 14 and the idle smooths out. I feel like this is probably my own doing and I've messed something up. I checked out the wiring for the neutral safety switch and it looks* fine. Any ideas on where to look?

*** the voltage was dropping when I shift into drive before I swapped out the alternator. Its still doing it after also.

I disconnected the radio and dash lights I had recently installed and the battery still drained completely within 24 hours.
 
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I would think it's a bit normal with a Denso to have the voltage drop a bit when you go into drive. The idle drops when you do that and the Denso is reacting to that. It should be fine once you rev the engine and drive.
As far as the battery drain. I would start by putting a amp meter in series with the negative battery terminal. See what the drain is. Then remove fuses one by one till the circuit is found and you'll see what fuse the drain is on. If you have more than one wire on the right side of the fuse. Remove one at a time till you get the troubled circuit.
If none if the fuses change anything. Then it's time to check circuits that get power without the fuse box like something that is connected to the left inner fender power distribution connection.
 
I had a similar voltage drain on a 1973 145E many years ago. In that car's case, it was the negative battery cable, which only goes to the battery tray on a 140, relying on the thick ground strap going between the body and the engine underneath the car. I grabbed a spare 240 negative battery cable, ran one wire to the battery tray, and the other to the side of the block. Problem was fixed, after eight months of dealing with jump starting it whenever I needed to move it or drive it, after it had sit for a day. It started doing this after I'd forgotten to turn off the cargo area dome light one evening, only discovering that it was on after our power had gone out during a snow event.
 
I took @dl242gt advice and pulled fuses with my multimeter in line with the negative battery cable. I found fuse #7 - fuel pumps - to be the culprit. I checked out the 2 relays and it seems like i may have swapped them when I was first having my no start issue. I put them in the right spots and the voltage seems to be back to normal. These relays are confusing to me since they are both very similar, but I guess one keeps the circuit open?
 
Ive been driving my car more recently. Its idling and running better than ever. I have noticed since I replaced the fuel injectors and other little things in that area that occasionally when I go to start the car I hear the fuel pump start to run with the key on. Not just for a second, its coming on staying on as long as the key is turned. This never happened before. This doesnt always happen either, just occasionally. Then I drove to Walmart the other day and after maybe 20 mins of shopping it took me like 5 or 6 tries to get the car started again. This time no pump noise when the key was on. Im wondering if I have a loose plug on something under the hood? I did have to disconnect all of the fuel system components when I removed the intake. Failing fuel relays? Failing in tank pump? It starts up right away 80% of the time - id love to get that % higher
 
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