2003 Saturn LS

On certain vehicles, a failure of the ignition control module may cause deterioration in idle quality, reduction in overall engine power and the vehicle may be hard to start.. Continued operation of the vehicle after such an ignition module failure will result in the "Service Engine Soon" light flashing, and may lead to secondary failures of the catalytic converter, oxygen sensor, and exhaust resonator. Failure of the resonator will cause increased exhaust noise and prolonged operation of the vehicle following a resonator failure may lead to an undercar fire. Correction: Dealers will (1) replace the ignition control module, or (2) replace the ignition control module and spark plugs, or (3) replace the ignition control module and spark plugs and update the powertrain control module calibration.