The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post

Bruno13 · 09-03-2017, 04:22 PM

Thanks Gary. Yes, both were spraying on initial start up, and longer if we kept feathering the throttle. At least until this morning when I tried to screw something else up

Wiring on this truck has been messed with for years when I bought it. Lots of splices with electrical tape, even some with masking tape! The 4 wires we discussed, the injector wires, had all been spliced. When my problems started happening, I tried to recall everything I touched before the "no start" problem. One of them was putting these 4 wires into a plastic loom to make it look better. While pondering last night, I thought I would check each of the connections of these wires today. I took the loom off, unspliced each of the wires, respliced them correctly, and put heat shrink on each connection. Somehow, in doing this, I screwed up something else. Went to start the truck and it tried to fire up twice, like it has been, then wouldn't fire at all. Tried to fire it off original working gas tank, and nothing. Come to find out I had a big gas puddle under truck because fuel switch was not connected because we bypassed it yesterday. Doohhh! Hooked fuel selector valve up again, and still no attempt to fire at all.
Next, I checked the fuses. I have a fuse labeled ECMB 10A which was blown. This never blew before. I replaced it, and it blew immediately upon cranking again. Moved to 15A fuse, same thing.
Checked under hood again and noticed a pretty crappy ground wire coming out of the ECM? harness and grounding on the Alt bracket, along with another ground. It had been spliced twice, was oily, and ground bolt was loose, so I thought I found my culprit. Put on new connector, cleaned up ground, and NO change once again. No injector spray at all, and fuse still blows.
Im not sure what I could have done just by resplicing those 4 wires, and cleaning up a ground, to make this keep popping a fuse. Even with fuse blown, I could hear fuel pumps working, so those, and the fuel relay must still be ok. Just no power to injectors now.
I've posted some pics of the wiring, ground connection, etc. If anyone has a clue of what is going on, please chime in. I'm moving backwards on this project and I'm willing to bet it is just something simple and stupid.
Thanks
OOPs. can't post pics because they are on my hard drive, not the web.

09-03-2017, 04:22 PM	#16
Bruno13 Registered User Join Date: Jul 2014 Location: Mooresville, NC Posts: 20	Re: 87 R10 stalls immediately after starting Thanks Gary. Yes, both were spraying on initial start up, and longer if we kept feathering the throttle. At least until this morning when I tried to screw something else up Wiring on this truck has been messed with for years when I bought it. Lots of splices with electrical tape, even some with masking tape! The 4 wires we discussed, the injector wires, had all been spliced. When my problems started happening, I tried to recall everything I touched before the "no start" problem. One of them was putting these 4 wires into a plastic loom to make it look better. While pondering last night, I thought I would check each of the connections of these wires today. I took the loom off, unspliced each of the wires, respliced them correctly, and put heat shrink on each connection. Somehow, in doing this, I screwed up something else. Went to start the truck and it tried to fire up twice, like it has been, then wouldn't fire at all. Tried to fire it off original working gas tank, and nothing. Come to find out I had a big gas puddle under truck because fuel switch was not connected because we bypassed it yesterday. Doohhh! Hooked fuel selector valve up again, and still no attempt to fire at all. Next, I checked the fuses. I have a fuse labeled ECMB 10A which was blown. This never blew before. I replaced it, and it blew immediately upon cranking again. Moved to 15A fuse, same thing. Checked under hood again and noticed a pretty crappy ground wire coming out of the ECM? harness and grounding on the Alt bracket, along with another ground. It had been spliced twice, was oily, and ground bolt was loose, so I thought I found my culprit. Put on new connector, cleaned up ground, and NO change once again. No injector spray at all, and fuse still blows. Im not sure what I could have done just by resplicing those 4 wires, and cleaning up a ground, to make this keep popping a fuse. Even with fuse blown, I could hear fuel pumps working, so those, and the fuel relay must still be ok. Just no power to injectors now. I've posted some pics of the wiring, ground connection, etc. If anyone has a clue of what is going on, please chime in. I'm moving backwards on this project and I'm willing to bet it is just something simple and stupid. Thanks OOPs. can't post pics because they are on my hard drive, not the web.