That, and ALL the truck's OTHER details need to be in your signature so they appear automatically with each of your posts, as this caption explains:

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No, that's not obvious. What's obvious is that someone has replaced the battery clamp with a REALLY cheap, low-quality, problem-prone one. Read the captions in this photo album:

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That's not surprising. Ford only used so many connector shapes on these trucks, so you can find that same shape in many places.That's EXTREMELY dangerous. You could burn up any number of components, the connector pins, the wiring harnesses, or even set the truck on fire.What diagram? I recommend the Haynes manual, but there are several editions. Read this caption:

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Why? What test did the previous one fail? Did the replacement pass the same test? What are the brand, PN, & source of the replacement?This & the NEXT several pages list the standard Ford colors for circuit functions:

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Find the first wire's color, make a list of possible functions, and look for similar functions in the lists for other wires in that connector.
No, changing a sensor fixes NOTHING, other than getting rid of a previous sensor that fails a test. So unless yours has failed a published test, leave it alone. Same for EVERY other part on the truck.Light bulbs are known to fail. All the time. And they're cheap. But you don't change them until there's a specific reason. Same for EVERY other part on the truck. And the factory parts are the highest-quality ones you'll ever have, so the longer you keep them, the better the truck will run.

If you suspect a part has failed, DIAGNOSE it. It's cheaper, quicker, & more-effective than blindly replacing it. For the IAC, read this:

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For every other part: until it's due on the maintenance schedule, leave it.

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That'll be a lot of work & money for no benefit.

 

I'm new here. It's been a while since I've been on car forums but the flaming is no surprise. I'll fix it.

Really? Both two wires from the O2 sensor wired directly to battery isn't obviously wrong to you? We are talking about cars/trucks, right?
Yes, I know the terminal is cheap and I don't like it. You should have seen what was on there before. I intend to replace it.

When I made the first swap, the colors of both sides of the connector matched. Seemed like it was worth the risk and it was. Truck runs absolutely perfect now with no codes of any significance.

I have the blue Haynes as well as the Chilton. They have the same wiring diagrams.

I replaced it because I had the No O2 Switching detected. Yes I know that was throwing parts at it, it's my money. Considering that it had been running for a significant amount of time without being powered, it probably DID need replacement in addition to the wiring problem it had. The replacement was a Bosch, no need to report the part # because as I said the truck is running perfect now and the O2 code has cleared. I've been about 40 miles and I KNOW that I could still get a continuous memory code. Until then, I'm going to drive it and run diagnostics reguarly.

Maybe you didn't see but I've fixed all the sensor issues.

Negative. I'm going over this truck. The steering shaft isn't on the maintenance schedule but it needs replacement.

 

I'm not sure if the Mustang MAF conversion kit can be used. https://lmr.com/item/PMA-EMAWH/1986-...Wiring-Harness
If not, no big deal, I don't plan on making it a race truck but I'd like it to have a little more *****

Surely you know that you can't make changes to the air entering the engine (heads/intake/etc.) with a speed density setup. Does that now qualify as a benefit???

 

You don't seem to know what flaming is. Giving you a suggestion about how to get relevant answers quicker isn't.Even on a new vehicle, the OBD system barely scratches the surface, and reading fault codes doesn't count as diagnosis. On these antiques, fault codes only flag a few critical circuits that are grossly out-of-range. They're not particularly useful for identifying - or even detecting - subtle driveability issues.

The ENTIRE list of codes that apply to these trucks (except '96) is in this caption:

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Note how few there are; even among the 3-digit group. Yours uses 2-digit codes.You seem to have skipped my previous suggestion, before the one you quoted. The first step in diagnosis is visual inspection. If something's busted, that's a fail, and it needs to be replaced.

For every other part: until it's due on the maintenance schedule, leave it.The air entering all my speed-density engines changes all the time as I drive. They work fine. If you're not changing the pistons to a substantially-different size, or adding forced-induction; you're not changing the amount of air entering your engine, regardless if it's speed-density or MAF. So, no: there still won't be any benefit.

...and don't call me Shirley.

 

Yes, the air entering speed density changes all the time. Obviously the motor doesn't run at 2K RPM at all times. However the ECU doesn't know how much air is ACTUALLY coming in. It's only figuring it up based on algorithims using other the other sensors. Therefore, if you induce more air into the system, IE bigger heads/intake/high lift or longer duration cam, the motor will continue to use the same calculations as before resulting in a lean condition. You're a Bronco Guru? Maybe you just aren't into modifying and stay stock? How can a "guru" not know this?

Let me guess, you're the guy on the forum that just likes to argue for the sake of arguing????

 

If you can't read, I can't help you. Good luck.