check heater plug control box is working ok get a meter set to 20volt dc range put one end on any heater plug, other end on a suitable earth get someone to turn on ignition but not start engine observe voltage should go to 12volts when ignition turned on after a while relay should de energise and volts drop to0 volts proving that relay is de energising check all connections are tight including all earths and batt connections good luck
get someone to operate acc pedal while you look at business end on pump is it returning to its rest position if not try spraying with wd40 good luck !!!
