So long story short bought a truck and the people weren't upfront about it all. Bought a 99 f150 and swapped transmissions. Still wasn't running right. Guy at o rielys said to swap the pcm as well that it's necessary because the tranny was out of the other truck. Truck doesnt start now. Its trying but wont fire up. Prior to swapping the pcm had issues with not wanting to go over 40 and no first. Begining to think the ex put the tranny in wrong and the linkage is messed up.. Help?? This is the first time I've ever done much more then a oil change..

 

You can't randomly swap PCMs. If the PCM isn't compatible with the truck or the engine it isn't going to run. Taking advice from someone at an auto parts store almost always leads to problems. I've NEVER found one that knew what they were talking about. I had one auto parts store guy tell me that there is no such thing as a transverse engine. All crankshafts run fore and aft, none are across the car. SMH.

Go back to the original PCM. Now find a wiring diagram for your truck, and one for the connector to the trans that you installed. I'll bet there is a difference in the connector and some of the pins need to be moved to get it to work properly.

 

Alrighty. Can swap it back no problem. My ex used the wiring harness from the original tranny as the new one was slightly different.. New sylinoids and such. Im not truck savy but Dont wanna give up just yet. Willing to try anything as long as I can find a step by step