We just switched 4.6 motors between 2 trucks. First time ever taking on this big of a project! We took at good one out of a 1999 f-150 4x4 and put it in a 1997 f-150 2x4. It went ok and the truck is running good but the check engine light is on. The scan tool say the IAT is -40 and the coolant temp sensor is also reading -40. Any ideas? Thanks for your help! Is there anything else that would be different between the 2 motors?

 

97 has 2 coolant temp sensors. You need to use both. As for the iat it could be related. Not sure.

 

Thanks for the help. Any idea where the Coolant temp sensors are located?

 

I found where the coolant sensors are on the old motor. You are right, two on the 97 and only one on the 99 motor. Any idea how to change the wiring so it works?

 

I used the 97/98 wire harness and plumbed in another connection point for the other sensor. I don't know of another solution.