Wiring harness help
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Wiring harness help
I recently replaced my wiring harness / valve cover gasket on the passenger side of my O2 7.3, I discovered today that The entire bank is not working. My question is should I Look anywhere else besides my own wiring connections, for a problem? Such as a fuse or maybe another plug somewhere? I’ve replaced about $1000 worth of parts chasing down this problem...I’m afraid if I spend another dollar my wife is going to ask for a divorce... lol
Fleet Mechanic
Joined: Apr 2019
Posts: 1,737
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From: South AR
I recently replaced my wiring harness / valve cover gasket on the passenger side of my O2 7.3, I discovered today that The entire bank is not working. My question is should I Look anywhere else besides my own wiring connections, for a problem? Such as a fuse or maybe another plug somewhere? I’ve replaced about $1000 worth of parts chasing down this problem...I’m afraid if I spend another dollar my wife is going to ask for a divorce... lol
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So no fuses or other plugs could be the culprit? Or a relay? I’m really hoping I have to track down a wire and NOT a fuse, I’ve been on top of, underneath of, this truck for two weeks, I’m excited to know where the problem is after replacing two injectors, hpop line and fitting, hutch mod in the tank, hpop valve, and a camshaft sensor...
It's a Van Gogh
Joined: Feb 2010
Posts: 7,813
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From: Elk Grove, CA
Welcome to FTE! 
Do you have a way to pull codes?
When one side goes down that can be caused by loose connections under the valve cover. Google 50 cent mod. The IDM will shut down the entire side to protect itself.
Also X2 with Walleye on checking the underside of the wire harness that goes across the driver side valve cover. It can chafe and cause shorts.
Which 2 injectors did you replace?
Do you have a way to pull codes?
When one side goes down that can be caused by loose connections under the valve cover. Google 50 cent mod. The IDM will shut down the entire side to protect itself.
Also X2 with Walleye on checking the underside of the wire harness that goes across the driver side valve cover. It can chafe and cause shorts.
Which 2 injectors did you replace?
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I replaced one, three, five, seven. I did five and seven a few months back at that time I replaced the valve cover gasket which comes in one piece with the wiring harness on it, it also came with a pigtail to wire into The main harness. I do not have a way to pull codes. Sounds like I’ll be tracing wires tomorrow... It doesn’t seem that there’s a fuse anywhere to be checked?
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Hotshot
Joined: Mar 2014
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From: Douglassville, PA
Check for pinched wires under the VC with that new UVCH. I have read where this has happened in the past.
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Cargo Master
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From: Snohomish, WA
The injectors are fired with a ground signal from the IDM, so each injector has it's own ground to accomplish this. The power is through a single common wire that is high voltage. If your whole bank is dead, then I would assume it is the power wire. The wires all go through the 42 Pin Connector on the Drivers Side Valve Cover then to the IDM in the drivers side fender well area.
Here is a link to the Injector Circuit to show you the schematic. The only fuses or relays are for the PCM and IDM.
Here is another link for the Injector Circuit
Here is a link to the Injector Circuit to show you the schematic. The only fuses or relays are for the PCM and IDM.
Here is another link for the Injector Circuit
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Sir you were absolutely correct, I traced the power wire back to the connector from the pigtail and discovered it had came loose, I also found out the connectors I used on the pigtail were insufficient for the voltage on the wires, it would seem they were leaking/arcing Voltage to one another causing the PCM to shut it down. I can’t thank you enough for your input it really saved me!
Cargo Master
Joined: May 2010
Posts: 3,047
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From: Snohomish, WA
Sir you were absolutely correct, I traced the power wire back to the connector from the pigtail and discovered it had came loose, I also found out the connectors I used on the pigtail were insufficient for the voltage on the wires, it would seem they were leaking/arcing Voltage to one another causing the PCM to shut it down. I can’t thank you enough for your input it really saved me!
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