L-Series OHV Engine - Engine Will Not Shut-Off

Recently a technician contacted the Tech Helpline asking for information as to the cause of why the engine in a customer's hatchback does not shut off when the key is removed. The technician found that the PTC wire (choke heater) had been connected to one of the duty solenoid wires in a previous repair attempt. Since the PTC was hooked-up directly to battery positive and not through the relay to the ECU, the ignition switch was bypassed and the wire feeding current to the duty solenoids also feeds the positive side of the coil causing the engine to remain running even when the ignition is off. One possible explanation as to why the PTC was attached to the duty solenoids is the choke may have been staying on fouling the spark plugs. Remember the PTC (choke) is turned on and off by the ECU which is looking for a tach signal from the distributor magnetic pick-up coil. If pick-up coil signal is weak or non-existent, the following components may be affected:

ECU - memory showing vehicle I.D. code Fuel pump operation KDLH solenoid automatic transmission Choke (PTC) ASV (Air Suction Valves) on all the time

If you think you may have some of these symptoms call the Tech Helpline for more information.