Nevermind.. Check Engine Light...

I just sold my C5 that I could never seem to get rid of that pesky little thing. I realy hope it doesn't come back..

 

CEL = CHECK ENGINE LIGHT


And yeah, scan for codes... don' t do the battery trick unless you recently worked on the car, and you know what wire you left out.. so you plugged it back in but the lights still there

If that made any sense

 

I would honestly be more worried if the CEL went off in my car lol, my CEL has been on for about 10K miles now.

My cars got 152K and running great so like everyone else says, once you mod, 99% of the time your doomed to a CEL even if there is no real prob. Yopu gotta remember CEL=$$ to a dealer so they will make it come on for the stupidest ****... like filling the tank with the car running.

 

So i got it scanned yesterday,
failing O2 sensor and a misfiring cylinder?

 

Got the exact codes?

Inspect the cylinder that is misfiring. Look at the plug, see what it shows, try swapping coils see if it follows the coilpack.

Clear the codes then, see if the 02 comes back or not, see if the misfire has moved.If so, replace coilpack, clear and try again, see if 02 comes back. If so, post exact code and we'll see what you need to do.