Thread: cylinder 1 misfire

Hey y'all I'm getting a flashing check engine light after doing a coolant flush and I can't figure out why this would be happening? Just got this car, 04 gtp comp g with 148k miles and the coolant was very dirty so I flushed good with a hose, did an oil change and supercharger oil change while at it, along with 180tstat and took for a small drive and when I got a over like 50mph I started getting the flashing check engine so hooked the scanner up and came back as a cylinder 1 misfire...any ideas as what could have caused this? I did spill alot of coolant while trying to burp my system and also dumped a bucket of water around the radiator fill which might have drenched part of my coil pack/cylinder 1 spark plug...could this have caused the misfire somehow?? Where should I start?

Pretty sure you just described what the issue is with spilling water/coolant over the coils and #1 cylinder. Dry it all out and see what you get. And don't beat on it when the CEL is flashing as that indicates a misfire that can destroy the cat converter.

Hey thanks for the reply...so I did dry it up and let sit overnight and thought it went away...went for a good drive and after about 30 miles or so, the flashing CEL came back while traveling up a small incline on the freeway...only lasted a few seconds and then went away again.. surely this can't be because I got the coil/ cylinder wet after this much time right? Any other ideas? I've ordered a coil pack to try that, and waiting on my wires to come in and will change all that and see what happens but is there anything else that comes to your mind?

take one of the other coils and flip it. see if the misfire stays on cyl 1 or moves with the coil. If it moves then you have a bad coil pack. OEM coils are best and can be sourced cheap at a JY. Also, if the plugs haven't been changed then I'd do that too along with the wires. Just stick with the stock AC Delco or NGK plug type and don't run platinum plugs on these cars as they don't get along.

Gotcha I will try that while waiting for my new coil...I did order an NGK one from rockauto as I know they are usually a good brand, do you think it'll be ok for the gtp though or should I get an ac Delco/gm original instead? And as for the plugs I got some iridiums are those good to use?

iridiums are fine and are OEM IIRC.