Hi, i'm new to this board, i saw u in the fast ford u all seem to have pritty tidy motors . Anyway i have a prob with my rsi, it misfires after about 10 to 15 min of hard driving until the ignition is turned off then back on, this seems to cure it for another 10 mins. The prob started after it going in for new sills and an MOT. I talked to a guy who was a ford dealer he said that the current from the welder might have screwed the ecu. I had an xr3i dizzy lying about so i stripped the ecu and the twin coils and swapped for the 3i dizzy. Now the car goes for slightly longer before the misfire starts but the misfire is still there . The other thing was the alternator was changed while it was in for the MOT could this be the problem? Any suggestions would be greatfully recieved.