po300 multiple cylinder misfire.

[zzcamaro00]

i pulled the wires (accel 8MM) off the coil packs while the car was running. spark coming from each one. now when i went to take off cylinder 5 wire the motors idle didnt change. bingo right?? i pulled the plug and nothing. i figured piston slap damaged it. NO DAMAGE TO PLUG. now i forget what does it mean when the plug is red rusty looking? the plugs are TR55 NGK's iridiums. SERVICE ENGINE LIGHT blinks when im really dogging it above 80mph or so:rant:. my hypertech tuner is indicating PO300. i returnd the computer back to factory specs and im waiting for anything to pop up. any input guys?

[97rs4life]

Re: po300 multiple cylinder misfire.

have you checked your cat to see if it is glowing red or rattling?

[ssms5411]

Re: po300 multiple cylinder misfire.

Red rusty looking , I would think water has been leaking somewhere. How does your other sparkplugs look and smell? I would replace the spark plugs, and make sure the gap it correct. Check the wires to see if any are melted and go from there. I would also check the spark plug of the red and rusty one again to see if it smells like anitfreeze or any other plug that looks the same. Also have you been low on coolant any? Have you cleaned to engine bay recently with water?

[loser]

Re: po300 multiple cylinder misfire.

you said when you pulled #5 nothing changed, is that clyinder firing? dirty/clogged fuel injector/s?

you can usaully tap on your cat to see if its bad.

rusty looking plug could mean water/coolant, like SSMS said, pulled the rest and take a look.

edit: check all the plug wires good, it doesnt take much to cause a misfire. little burns in the right spots can do more than you think

[ssms5411]

Re: po300 multiple cylinder misfire.

^ thats true, forgot about the fuel injectors, a bad one can cause a random misfire, I had that problem before.