P0300 - Random/Multiple Cylinder Misfire Detected
The flashing Check Engine light indicates the most serious of conditions. Too much raw unburned fuel is going into the exhaust system where it will overheat and damage the catalytic converter. If that occurs constantly, you're supposed to stop the engine right away before that damage occurs.
The spark plugs are a good suspect, but you also have to consider compression, mismatched injector flow rates, (more of a problem on GM cars), fuel quality, and ignition timing. There isn't much you can do without a scanner to look at live data and fuel trim numbers.
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Thursday, December 10th, 2015 AT 12:48 AM