Good afternoon,

I have recently had a new engine fitted to my Fiesta Zetec 03, due to timing belt snapping.

The engine I had fitted was from an 07 fusion (matching engine code), since having it fitted the engine management light has been illuminated, either constant or flashing. Having checked this out the ECU is registering a random misfire but the engine is not misfiring and is running fine. The light comes on at about 2500 rpm!

I have called my local Ford dealer and they just said they would plug it in and run a diagnostics test. Before I do this does anyone know if there is a software update available or whether remapping would get rid of this error. (I am just relaying what mechanic has suggested, I do not claim to be an expert , or know really what I am talking about)

Any help or suggestions would be greatly appreciated.