Affordable Fuel Injection (1 Viewer)

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Thanks. I'm willing to try anything.

Using an Accel coil, the standard size yellow one. Tried another one (known good) just like it and no change.

I have not measured anything with the distributor. I don't know what to measure and what the correct specs should be.

I did notice that when I did get the injectors to spray fuel, that it was sporadic. Not consistent like it would be with each individual spark plug firing while cranking. I'm about convinced it's a distributor issue.

I talked with Norm again today, and he's just as confused as I am. We talked about a few more things to check, and if that doesn't work im gonna have him send me a new distributor.

Thanks for the help.
 
Thanks. I'm willing to try anything.

Using an Accel coil, the standard size yellow one. Tried another one (known good) just like it and no change.

I have not measured anything with the distributor. I don't know what to measure and what the correct specs should be.

I did notice that when I did get the injectors to spray fuel, that it was sporadic. Not consistent like it would be with each individual spark plug firing while cranking. I'm about convinced it's a distributor issue.

I talked with Norm again today, and he's just as confused as I am. We talked about a few more things to check, and if that doesn't work im gonna have him send me a new distributor.

Thanks for the help.
Did you check the 2 pin connector on the ignition module that goes to the distributor for looseness?
 
Thanks. I'm willing to try anything.

Using an Accel coil, the standard size yellow one. Tried another one (known good) just like it and no change.

I have not measured anything with the distributor. I don't know what to measure and what the correct specs should be.

I did notice that when I did get the injectors to spray fuel, that it was sporadic. Not consistent like it would be with each individual spark plug firing while cranking. I'm about convinced it's a distributor issue.

I talked with Norm again today, and he's just as confused as I am. We talked about a few more things to check, and if that doesn't work im gonna have him send me a new distributor.

Thanks for the help.

Pop the rotor off and you’ll see the trigger wheel. Should have 6 evenly spaced teeth. The vr sensor has 2 wires running to it and is fixed on the distributor around the trigger wheel. Should look like a small magnet. Adjustable via a screw just like a points distributor. I’d start with .2mm or (.008in). The closer it is the greater your signal just make sure it’s not so close that it strikes the trigger wheel.
 
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This is what the ignition module connection looks like. 2 wire connection to coil, 4 wire connection to distributor.

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So, another finding....

when I take a spark plug out and ground it, it will crank and run the first time I try it, no matter the spark plug. However, once I cut it off after 30 seconds, say to try something else, it will not run again, even with the same spark plug grounded. It will run once, and then not until way later, usually the next day.

The injectors only fire when cranking once per revolution, I'm assuming when the rotor passes by the grounded spark plug, whichever one that might be (I've tried all 6 individually, same result)

Also, for the first time today, when I got it running, the coil was arcing all over the place, bright arcs to both posts of the coil. While it was running, with a spark plug out and grounded, I removed the grounding wire from the spark plug....it idled down a bit and wasn't as smooth, the arcing of the coil continued as well. The arcing was not happening when the truck was running perfectly a few weeks ago.

will be digging into the distributor now
 
This is what the ignition module connection looks like. 2 wire connection to coil, 4 wire connection to distributor.

View attachment 1789153

View attachment 1789155
Their should be another connector on the other side of the ignition module. Their should be 1 2 pin weatherpack connector as you have shown, a 4 pin weatherpack connector as you have shown, and then a 2 pin non weatherpack connector on the other side which it looks like the plastic cover is hiding in your pic. Neither of the weatherpack connectors should be going to the distributor as far as I remember.
 
post #74, you can see the ignition module.

the non-weatherpack connection (2 exposed metal prongs) are inside the AFI plastic and aluminum housing. That is hooked up as well. That was the connection that you said check if loose?

and you are correct, the non-weatherpack connector is hooked to the distributor. The 4 prong weatherpack connector goes back to the main wiring harness and the 2 prong weatherpack connector goes to the coil. All connectors are unique and can't be hooked up wrong. All are connected just as they were when it was running fine, and also when I get it to run with my grounding the spark plug trick.
 
I know I'm new here, but I have had similar frustrations with similar equipment on other platforms. This sounds like a grounding problem to me; and that is reinforced by the fact that with the plug out, grounded to the frame, it will occasionally act different (run). I know there have been enough exceptions both ways to say it's happening 100% of the time but electrical gremlins seldom do. I don't mean to be captain obvious because I'm sure you've double/triple checked them already... but I can't get away from the fact that intermittent ground will cause every bit of the problems you are having. I'm following this thread with great interest. Good luck getting it lined out.
 
Could be a ground....thats where I started, and am still checking and rechecking all connections. There is one main ground from the AFI wiring harness and I have tried hooked directly to the neg. battery terminal, no change. I now have the ground back to where it was when it was running fine early on.

So, update...pulled the distributor....measured it to .008. Its very close to that.

spun the distributor by hand....got a very weak spark from the grounded spark plug, but the fuel injectors fired as fast as I could spin it and fuel pump ran as long as I spun it. Appeared to fire injectors for each 6 spark plug location. SO why won't it signal to fire the injectors when the engine is turning the distributor? The engine is turning over as fast as it usually does during normal operation, so I think the correct RPM of the engine is there to fire off the injectors.

Bad coil?
 
When I talked to AFI, they stressed (loudly) that the backside of the heat sink on the ign. module needed to be well-grounded. This is the black box mounted on your fender. I bought two grippy 'external-teeth star washers' and put them between the heat sink plate and the fender, so the star washers dig through the OEM paint on the inner fender and create a solid electrical ground. I then bolted through these washers to the fender using the provided holes in the module.

Looking at your pix, I see lots of fasteners, and it appears well-grounded, but you might check this ground again, since you seem to have ignition-related grounding issues.
 
post #74, you can see the ignition module.

the non-weatherpack connection (2 exposed metal prongs) are inside the AFI plastic and aluminum housing. That is hooked up as well. That was the connection that you said check if loose?

and you are correct, the non-weatherpack connector is hooked to the distributor. The 4 prong weatherpack connector goes back to the main wiring harness and the 2 prong weatherpack connector goes to the coil. All connectors are unique and can't be hooked up wrong. All are connected just as they were when it was running fine, and also when I get it to run with my grounding the spark plug trick.
Yes the exposed 2 pin plug on the ignition module is the one I'm talking about. See if it feels like the female end pins are not grabbing the Male pins well. May have to pinch the female pins tighter so they make better contact with the Male pins.
 
They said the same thing to me. I just added a dedicated ground wire to it, no change.

Re-installed the distributor and spark plug wires. Checked the ignition module. It's tight and grounded. Norm seems to think the module is ok due to the injectors spraying when I manually turned the distributor.

When it's all installed and hooked up, the injectors will not spray fuel. Why is this? The distributor will trigger fuel pump and injectors when I manually spin it, and a spark plug is grounded to the center distributor wire. Engine spins over fine when cranking, at it's usual RPM when cranking.

It's back to the original issue....the system only works when a spark plug is out of the engine and grounded to the block.

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Sounds like a bad connection somewhere to me. If the only difference between the injectors spraying and not spraying is that you pull the distributor and spin it to get the injectors to fire and then installed it doesn't work then it sounds like somewhere you have a wire or connection that is barely making contact and loses contact when installed.
They said the same thing to me. I just added a dedicated ground wire to it, no change.

Re-installed the distributor and spark plug wires. Checked the ignition module. It's tight and grounded. Norm seems to think the module is ok due to the injectors spraying when I manually turned the distributor.

When it's all installed and hooked up, the injectors will not spray fuel. Why is this? The distributor will trigger fuel pump and injectors when I manually spin it, and a spark plug is grounded to the center distributor wire. Engine spins over fine when cranking, at it's usual RPM when cranking.

It's back to the original issue....the system only works when a spark plug is out of the engine and grounded to the block.

View attachment 1789291

View attachment 1789292

View attachment 1789293

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Injectors fire with the distributor installed as well. All I have to do is take a spark plug out and ground it to the block, or any external ground. Then when I crank it (distributor rotating) it sprays fuel when cranking over. This leads me to believe (and Norm at AFI) that the distributor is operating properly. He believes the ignition module is OK as well, since it senses the distributor signal and fires the plugs and turns the fuel pump/injectors on when cranking (with spark plug externally grounded).

When all the spark plugs are installed and distributor connected, no fuel when cranking.

The only thing that I can see that could POSSIBLY be out of wack is the spark I see is quite weak. However, the battery is fully charged and I've tried another identical coil that I know works. I do not know what weak spark means to the EFI system. Or if it's truly 'weak'.
 
well....change of plans.

I was going to try another ignition module (I've changed it out once before), but when I disconnected the 2 wire weatherpak connection, it popped and smoke came billowing out from under the dist. cap. So of course I freaked out. Took the cap off, and the wires inside the distributor are fried. I've taken this connector off many times before in my troubleshooting process. Not sure what happend this time.

So, I'm gonna see if Norm will send me an HEI style integrated distributor to try. My current one is now toast.

Everything has been hooked up the same way each time. Never seen something explode when the wire is taken OFF.

Will report back as I get news. Or give up and put the carb back on. At least it ran then.
 
The spark I saw when cranking with my AFI system appeared/appears very weak during cranking. Barely visible with the naked eye. Truck runs perfectly, in spite of that.

Hang in there - you'll get to the bottom of this.
 
Thanks. Good to know about the spark. Mine seemed to be sufficient, as it would randomly run with a spark plug grounded. It wouldn't be so frustrating if it didn't run great for a week and then stop suddenly.

It's quite possible that I'm overlooking something, I may get some fresh eyes on it when I get a new distributor.
 
Electrical gremlins are the bane of my existence. Keep at it however. EFI was the second best thing I ever did to my FJ40. The first was a dual battery setup running a refrigerator full of beers.
If I was closer I’d give you a hand AND a beer.
 
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