Ford Repair: no heat & temp. gauge not working. (98 f-150), temperature reading, engine swap

Question
recent engine swap and after a few hundred miles we have no heat & temp. gauge not workin. just replaced thermastat. any suggestions?

Answer
Well, you should start with the temperature sensor, and or switch. The check engine light should be on. Have the odes retrieved. Also, you computer sees the same thing you do, and it will attempt to run the engine within the operating range of any temperature reading or lack of, so don't make it a daily driver until you fix it. If necessary, as a last or first alternative, would be to buy a set of aftermarket gauges.