So, we swapped a low miles engine into our 2000 V4 after an overheat killed the original. It runs great, better than ever, but will not shift into overdrive. At 70mph it's turning 3K rpm, much higher than normal. So, did we bump something, forget to connect something, offend the shifting gods? We are at a loss to know what happened.

 

Are you getting any CEL? If the engine is not getting to full operate temperature, or if the computer doesn't think it is (ie failed coolant temperature sensor), it may not go into overdrive.
Stan

 

I checked tonight and found three codes, P0102, P1107, and P1106.

 

Sensor readings can affect how the transmission behaves. For example, if the coolant temperature is low, the tranny may not go to overdrive. I have seen this happen in winter and it does this to warm up the engine faster. I don't know all the logic in the TCM but the codes for the MAF and barometric pressure may also prevent the tranny from going to overdrive.

Try to resolve the MAF issue and see if that corrects the tranny issue.

 

I was able to work on the V40 this weekend. The trans fluid was a bit low, but not much. I topped it off. The engine temp sensor was replaced with new which corrected the fan from coming on whenever the key was turned, even if the engine was not run. Car runs great, but still pulling 3K rpm at 70mph. Appears that overdrive is not working still.