P1351 after replacing ignition coil and icm

[doncaruana]

Good Work! These can be a pain to find. You got thru quicker than most.
Try this or alternate numbers-

More Information for UNITED MOTOR PRODUCTS CON76

As my buddy told me - you already have the equivalent of what's in the junk yard. Buy a new one.

 

[doncaruana]

So...update...I'm an idiot. The reason that one pin was dead is because I had disconnected the other end that goes to the coil when I tested it. That's why I couldn't duplicate it. However...

I decided to test the actual ignition coil while I was at it. You're supposed to check the resistance in 3 places. Well, the resistance between the outer most pins (B and C) is essentially supposed to be about zero (technically the manuals say 0.1). On my just pulled out of the box AC Delco ignition coil, it's a flat 0.5 no matter what. But on the Autozone one that's in the truck, it meters all over the place - 0.9. 10, 1, 25, 1.5, 50... So I'm gonna try and change that coil out...

 

[doncaruana]

And problem still exists. The only thing I never checked was the vcm, but it just doesn't make sense why it would suddenly have an issue. I didn't really check step 3 where you monitor the voltage coming to ICM B while cranking because the next step on that was unplugging the VCM, etc. But, strictly speaking, if I'm following the troubleshooting guide, that's really about all there is left. Although I could consider using a piercing probe to get the resistance of the line without actually taking the connector off - that is if I can even get to it (I think the one I need to get to is one of the bottom ones).

When the weather warms up again, I guess I'll get out there and jiggle the hell out of the wires and see what I can see. I've replaced the autozone icm and coil with ac delco ones already. I'm just so disappointed I can't put words to it.

 

[exp500]

Check your grounds, check computer plugs for corrosion.

 

[doncaruana]

Check your grounds, check computer plugs for corrosion.

Which plugs? You mean into the vcm?

 

[exp500]

All 4 of them. Look closely with a bright light, Corrosion/water/bent pins/loose connector.

 

[doncaruana]

That will be fun getting to them. Lol

 

[Tanner Peterson]

Hey!
I’ve got the exact same issue as you with the start and stall and the P1351. Did you ever come to any resolution?

I’ve tried so many things it’s insane… and this is happening to me on a new GM crate engine.

 

[doncaruana]

Hey!
I’ve got the exact same issue as you with the start and stall and the P1351. Did you ever come to any resolution?

I’ve tried so many things it’s insane… and this is happening to me on a new GM crate engine.

I still haven't resolved it. My next thing is replacing the connector to the brake control module. Just gotta find the time and weather to do it.

 

[exp500]

Don, don't sweat about the relearn if you disconnect computer. It fixes itself in 50 miles.I just wanted you to get everything else done before you got a it runs different.
Testing of the ABS connecter - use a 45 degree pick or similar to bend the femle contact a bit tighter.
Spray with contact cleaner and use dielectric grease. I grease the rubbers too.
Have you Tested ICM White wire? Try both ways- Test light grounded then connect to white wire and crank engine. Should flash strong every hit. Swap test light for voltmeter, crank engine.
Last test- when computer disconnected, Ohm test white wire Icm to Computer. Ohms should be about the same as 5-6 feet of 20 ga. I have replaced a couple white wires.