1992 Bronco 5.0 Oxygen Sensor Wiring Missing

[Bill_Morgan]

I'm nearing completion of my '92 Bronco 2 for 1 project (two new problems for every problem fixed) and have discovered the plug and wiring to which the oxygen sensor connects is missing. I've learned from the forum that that wiring should be running in the same loom as the starter wiring, but that isn't the case.

There is a four-prong plug, identical to the plug on the oxygen sensor itself, extending from the wiring harness just below the starter solenoid. The wire colors are gray/green stripe, orange, black, black/red stripe. It is a male plug just as the one on the sensor. Is it possible that a harness connecting these two plugs is the missing piece?

 

[L\Bronco]

Hi Bill, as far as I can see from the wiring diagram, you are looking for connector C- 1025 which should be taped to the big positive starter cable down by the starter, and C-1003, which should be the at other end of the starter cable by the battery. As you suspected, it looks like they connect the 2 together. The location view is a bit hard to read but it shows C-1025 and it appears on top of the engine, but its actually under, near the starter.
Hope that helps
Cheers

 

[Bill_Morgan]

Thanks! I studied the illustrations, then went to my local Wrench-A-Part for a real-life look. I found the connecting harness that's missing from my truck still in place on two '92 F150s and got it off both. It connects the plug in my photo to the plug of the oxygen sensor. The harnesses were of slightly differing lengths, so I'll use the one most suitable to my application. That is the last piece needed before attaching the exhaust and starting the Bronco for the first time in 12 years.

I eventually will compose a post detailing this restoration process. I've encountered manifold disgusting instances of sorry workmanship, carelessness, oversight, and missing parts - perhaps more than in any of my other restorations through the years.

 

[L\Bronco]

Thanks! I studied the illustrations, then went to my local Wrench-A-Part for a real-life look. I found the connecting harness that's missing from my truck still in place on two '92 F150s and got it off both. It connects the plug in my photo to the plug of the oxygen sensor. The harnesses were of slightly differing lengths, so I'll use the one most suitable to my application. That is the last piece needed before attaching the exhaust and starting the Bronco for the first time in 12 years.

I eventually will compose a post detailing this restoration process. I've encountered manifold disguisting instances of sorry workmanship, carelessness, oversight, and missing parts - perhaps more than in any of my other restorations through the years.

Great news! Good luck with the fire up, hope it goes well!
(Some people shouldn't be allowed to work on vehicles. My current project (79 Bronco) came from a guy trying to either restore her or part her out, (I couldn't tell the difference from the state of the pile of parts and complete lack of logic in anything that was done.)
Way to save another one!)