FIX, hope so anyway, had the car back in this week, had to remove an air con low pressure pipe as it was leaking, to do this we had to remove the inlet manifold, noticed when this was off the pressure switch (swich set in rocker cover)connector plug securing clip had broken allowing the connector to rise off the switch and the wire to rub through on the manifold. A small blob of tiger seal, and all seems well so far. Thanks to Dave for suggestion, sorry late posting fix! phrom fil.