1993 Isuzu Trooper My service engine light was always coming on

Your car is equipped with a computer controlled engine management system. An independent auto service center can scan your computer for fault or error codes. The information should pinpoint the malfunctioning components. If a major tune-up has not been done recently, this could be the cause of your problem. Replace the spark plugs, plug wires, fuel and air filters, etc. Also, replace the oxygen sensor. In addition, service the fuel injection system. Clean the carbon deposits from the throttle bore and idle passages.