Questions and Answers

Another Ford Check Engine Light Q. 1991 Ford F150 66,000 miles 5.0 liter engine V-8 Fuel injected. My battery had an internal short and died when I left the truck parked for three days. Even the radio was deprogramed.

The Check Engine light will come on when I accelerate onto the Interstate, stay on for three minutes and go off and stay off. Is this just my "computer" relearning what to do, a coincidence with the 60,000 mile encouragement for the 60K service, or ...

All typical items are normal: oil pressure, engine temperature, alternator output in Volts and Amps both on the panel and by direct measurement at the battery, transmission fluid level...

CHL

A. The Check Engine Light (MIL) will not light up when it is "learning". What is happening is the computer is detecting a malfunction and turned on the MIL. The fact that it only comes on under acceleration and then turns off indicates that is when the problem occurs.

You will need to pull the DTCs from the PCM to see what it is and then we can start troubleshooting.

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