1994 Ford Ranger 3.0 automatic transmission I've dumped so much money into this POS trying to figure out what's wrong. I have it running good now, I've changed almost everything electrical trying to diagnose the problem I've got it somewhat narrowed down now.
I thought I found the issue at the fuel pump I had a code for faulty ground at fuel sending unit the wiring was burnt and extremely corroded so I changed the wiring pig tail and the fuel pump. Truck runs good until you move once you put it in gear it's fine once tires start to roll it starts to miss and has no power if I disconnect the speed sensor wiring at the back of the transmission seems to drive just fine other than won't shift into overdrive. initially truck would work fine and then occasionally go into a limp mode. I couldn't even drive it at all sometimes letting it sit for a few minutes or cycling the key all the way off and back on I can at least get it home usually but always seems to run fine in Park. I have already changed the speed sensor at the back of the transmission. the only code I can get to come up is bad ground at fuel pump sending unit I'm going to mess with that next but I don't think that's the problem because it drives when I disconnect the speed sensor at the back of the transmission, it seems to have something to do with the vehicle moving once the Driveline starts to rotate any ideas?

 

disconnect that speed sensor and Keep on Truckin.