Questions and Answers

Subaru Legacy Check Engine Q. Hi, I have a 1993 Subaru Legacy with 45,000 miles. A few months ago the check engine light would periodically go on and then go off after a few seconds. I took the car in for a tune up and they advised that there could potentially be a problem with the camshaft or crankshaft.

About a month ago, my car started idling higher than normal (between 2,000 and 3,000 RPM) and would not idle lower even when I tapped on the accelerator. The lowest it would idle would be around 1,000 RPM.

I recently went on a road trip - longer than my average commutes and one morning I had problems starting the car. Once it did start, the cooling fan came on immediately as did the check engine light. The check engine light remained on from that point forward.

Now, every morning, I have difficulty starting the car and the check engine light and cooling fan remain on. Would you happen to have any information as to what causes this condition to occur?

Thanks,
Rob

A. Your car has entered a fail safe mode. During normal vehicle operation, the ECU controls fuel, spark and emission systems. In the event of a sensor failure or inconsistency, the unit switches to "Fail-Safe" mode. In this mode, certain sensor and output parameters become "fixed," allowing limited vehicle operation.

In most cases, the "Check Engine" lamp is illuminated and trouble codes are recorded in ECU long term memory. These alert the operator that a system requires attention and guides the technician toward the failed system.

So, the next thing to do is to pull the codes from the computer and see what they are. Then we can start troubleshooting.