Hi guys

This has probably been mentioned in the past, but I couldnt find it after having a good look. If you can direct me to anything handy or answer my question would be very greatful.

I have a standard 53 plate st170, and the diagnostic light keeps coming on. The car has been to ford 2 or 3 times, and they've said that its a known fault with the st170 in that it will occasionally overfuel on the over-run, and the LAMBDA sensor/ HEGO sensor will pick up the unburnt fuel and log a fault code. This is ok, but its costing me like 30 quid a time to get the ECU reset when there isnt really a problem. The car has just had a major service and had the exhaust sensors replaced to try and cure the problem and its still doing it.

I've had a few escorts, fiesta's and ka's and on most of them if you leave the battery terminals disconnected over night the ECU will reset itself and clear any rough running/idling problems etc some of the time (with some luck lol ) I'm just curious if this is the same with the focus cause I've heard the PATS can kick in and cook the ECU if I'm not careful. Any help/guidance would be appreciated cause its starting to do my head in. Just wondered if leaving the batt terminals off for a few hours will clear it all, or whether its a case of getting hold of one of the diagnostic gadets they use, or if theres anything else known that will switch it off

Cheers

Dave