Hi all!

I've poked around the forum and I didn't see anything quite like my problem that has actually been solved so hopefully this can be the first!

Alright, so the back story is that I bought a little 87 ranger off a guy pretty cheap. The motor was rebuilt about 40k before I bought it but I had to replace the transmission as one of the clutch packs blew it's springs all through the tranny and made a horrible mess of everything. So I spent some time rebuilding the thing, put it back in and it still didn't want to work again. That's cool, I picked up a 83 bronco with a nice strong tranny still in it and swapped them. My truck is now back on the road, that's awesome.

Before changing the tranny's the ranger was getting pretty decent mileage I estimate 20-24 mpg. After though is a whole different story. I didn't notice anything right off in the first few days as I was babying the new tranny just to give it time to get used to being driven again (hadn't been used for about 3 years)

First time I noticed that it was flooding I was going up a pretty steep grade on the highway and all of a sudden, it lost most of it's power and started spitting out a huge cloud of black smoke. I backed off on the accelerator and when it got just past the top of the hill the engine picked back up and it stopped flooding. It has gotten worse since then.

I've done pressure tests on the fuel rail to see what pressure the regulator is putting out and everything seems to be fine there. I did notice a wire sheered off the O2 sensor, conveniently in the exhaust where no body can easily get to. So I replaced the sensor and my flooding stopped for nearly 2 days. I could still feel that when going up a steep hill and the accelerator was depressed closer to the floor there wasn't as much power as there should have been. I could hear it rev up then at a certain point it would feel like it was just borderline flooding, though no black smoke.
Now it's back just as before, though the sensor is intact and all the wires trace back and appear intact, I've done a continuity test on each of the 3 wires and they are good as far as I can see.

It's a fuel injected 2.9L V6, 4x4

I'm just curious if there's something else I can look at or if others have had this problem and can tell me what was causing it in their case.

I forgot to add that I replaced the air filter incase it was that not allowing proper air flow, also no change.

 

Maybe your cat is starting to clog up.

 

That's what my uncle thought too, but my truck doesn't have a catalytic converter on it.

I took the O2 sensor and unplugged it from the harness yesterday, cleaned the contacts, and plugged it back in and it hasn't flooded since. Maybe I got a little grease or something on the contacts when I put it in.

Thanks, for the response, hopefully that's all it was!