Changed Heater Core, now truck won't start.
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Changed Heater Core, now truck won't start.
My truck ran fine before I replaced the heater core, it ran while I had the dash out with the new core in to test for leaks, then I put the dash back in and now it's not starting. It'll crank, but not start. Fuel pump is not priming, but running a straight power wire to the pump causes it to turn on, but then it still won't start with the running pump.
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I don't see any blown fuses, all I can think is somehow one of the EFI relays got shorted out while I was putting the dash back in. Intake manifold ground is attached.
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I should've disconnected battery yes. ECU ground is fully connected, tested EFI relay, main relay, open circuit relay, and whatever relay is in the engine bay fuse box, all work. EFI fuse is not blown.
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#8
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Just how did you check the relays ??
Remove them use a 12VDC power source energize the coil check the contacts for continuity ??
Check voltage into the relay on both the contact side and coil side??
If you have a shorted relay you have open circuit protection or melted wires causing a open circuit
Remember a Short is current going directly to ground
Remove them use a 12VDC power source energize the coil check the contacts for continuity ??
Check voltage into the relay on both the contact side and coil side??
If you have a shorted relay you have open circuit protection or melted wires causing a open circuit
Remember a Short is current going directly to ground
#9
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Just how did you check the relays ??
Remove them use a 12VDC power source energize the coil check the contacts for continuity ??
Check voltage into the relay on both the contact side and coil side??
If you have a shorted relay you have open circuit protection or melted wires causing a open circuit
Remember a Short is current going directly to ground
Remove them use a 12VDC power source energize the coil check the contacts for continuity ??
Check voltage into the relay on both the contact side and coil side??
If you have a shorted relay you have open circuit protection or melted wires causing a open circuit
Remember a Short is current going directly to ground
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Found the first solution. The ignition fuse had blown and I overlooked it. It started right up after I replaced the fuse. I let it run a while and everything was fine. I put my speedometer and my radio back in, because I was going to run dashless in case something else happened. Which it did. After putting in the radio and the speedometer the truck won't start again. When I replaced the 7.5A ignition fuse I used a 10A because it was the only one I had on me, could I have just fried my ECU by using too big of a fuse? The 10A fuse is not blown now.
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So, the last issue was the EFI relay was loose. I took it apart, which apparently you're not supposed to do, so now the cap is loose and to start the truck I have to hold the relay into the fuse block then start it. Ordering a new relay ASAP.
#13
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Sounds like your EFI relay is loose in the socket .
The cap covering the relay is just to keep the dirt out and peoples fingers as well
Unless you broke something the relay should work just fine with the plastic cover removed
Most of my test relays the covers have been lost years ago
It seems your getting closer in anycase
The cap covering the relay is just to keep the dirt out and peoples fingers as well
Unless you broke something the relay should work just fine with the plastic cover removed
Most of my test relays the covers have been lost years ago
It seems your getting closer in anycase
#14
When you crank does the fuel pump come on? Did you plug in the circuit opening relay? Its above the ECM on pass side. Try using the diagnostic port as pet the FSM and see if the truck starts if you jump the pump circuit. Sounds like a plug didn't get plugged back in after the dash went back together possibly.
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