General Motors installed redesigned ignition switches without changing the part numbers on the Pontiac Grand Prix and other models involved in the June recall of 6.73 million midsize sedans, The Detroit Free Press reports. The company has already come under fire from lawmakers after it was discovered redesigned ignition switches without a changed part number were installed on certain small vehicles involved in the initial ignition switch recall in February.
As with the recalled small cars, such as the Chevrolet Cobalt, the ignition switch in the midsize sedans was discovered to be faulty and was subsequently redesigned, however the part number for the new switch remained the same as the old switch. This means that dealers may have unknowingly installed defective ignition switches while repairing cars that didn’t have the problem to begin with.
“It is possible that the old switch was used to service vehicles,” a GM letter stated.
Engineers redesigned the switches after owners complained their cars were shutting off suddenly. In redesigning the switch, they attempted to increase the amount of torque needed to move the ignition from the ‘on’ position to the ‘accessory’ position.
GM CEO Mary Barra said the practice of redesigning the switch but keeping the same part number “violates Engineering 101.”