CEL flashing; i don't know why
 

the CEL is flashing while i'm driving. i don't mean it's in diagnose mode. i replaced CTS, then cleared CEL codes. afterward, this is when i started getting the weird behavior. any ideas, gentlemen?

You have a misfire.

multiple mis-fires

I only had one, and it was flashing.

you might have left it in self diagnosis mode... happened to me a couple of times lol

the CEL flashes about 20 times, then stops for about 10-15 sec, then flashes again. does a misfire have a code? because my engine is running CRAPPY. engine very shaky/rough running. have to drive w/ tach higher than 3000RPM to make most of roughness appear to go away, until RPMs go under 3000 again. arghhh. if bad fuel injector, is code for that problem? i did replace all on rt. bank over 3yrs ago so maybe lt bank having a bad injector or two?

Go to autzone, and when the light blinks, press read. Stop guessing because you won't be happy if you guess 500 dollars worth of unessecary repairs. If you have a bad injector, I believe it can throw a misfire code, and a bad misfire is USUALLY the culprit for a blinking SES.