The Check Engine light means the Engine Computer detected a problem, set a diagnostic fault code, and since the light turned on, whatever that code refers to could adversely affect emissions. The first step is to read and record that code. Chrysler makes doing that yourself much easier than any other manufacturer. Cycle the ignition switch from "off" to "run" three times within five seconds without cranking the engine, leave it in "run", then read the numbers that show up in the odometer display.
There are varying degrees of severity that can be determined by how the Check Engine light acts. When it's flashing, that means stop the engine as quickly as possible because too much raw gas is going into the exhaust system and will overheat and damage the expensive catalytic converter. The least serious is when the light turns off by itself while you're driving. If it's a little more serious but the intermittent problem goes away for now, the light will only turn off after you turn the ignition switch off and restart the engine.
On '96 and newer cars, the Engine Computer can detect which cylinder is misfiring, and most likely that's what your fault code is going to say. The most common cause of misfires is spark plugs that are overdue for replacement.
Sunday, October 19th, 2014 AT 10:24 PM