car run fine except it idles a little rough sometimes but most of the time it runs great .All this started after driving in the snow.
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1999 Lexus ES300
Question: check engine light on alone with trac off
Answer #1patrick mannion from Greg Solow's Engine Room, February 09, 2010, 14:29Master
I usually see the ignition coils fail occasionally the fuel injectors but in either case no more common than any other make of car. If the Check Engine light/Service Engine Soon light illuminates while you are driving, the car's on board computer sees a fault in the engines management system that is causing an excess amount of pollutants to be emitted from your car. This could result in engine damage if left neglected. Some problems that can cause the Check Engine light to stay on may take two "drive cycles' to complete before illuminating the Check Engine Light. The computer sees a problem and looks for an identical set of circumstances to occur to confirm that it has indeed seen a problem before turning on the light. A Check Engine light that continually flashes while you are driving is serious and is a sign that the computer sees a problem that seriously risks damaging the catalytic converter which may result in an expensive repair or even may cause a fire! Diagnostic codes are stored in the vehicle's computer and can be retrieved using a scantool that communicates with the computer in your car. We have in our Repairpal website an encyclopedia with in depth articles about computer, and computer control systems, emission and driveability problems. http://repairpal.com/check-engine-light
With a Lexus some problems that cause the check engine light come on will also bring on the Traction control light.