On the Mk 5 & 6 escorts it is VERY common to find water making it's way down the A-pillar onto the tracks in the fuse box, and the soldering looks like it has been done by a trained monkey anyway!. This could cause a whole lot of very funny faults. My friends Escort had the washer jets come on for no reason, stutter at 4k RPM, Sudden stalling of the engine - then it fired up again?!?!? Window switches controling the wrong windows, e.t.c, e.t.c So if the voltage regulator doesn't fix it, that would be my next bet.