p0303 misfire code
12-28-2019, 02:58 PM
#1
Rennlist Member
Thread Starter
p0303 misfire code
Took my 2011 7.2 RS out for a little highway run on Christmas day. Hadn't driven in the car in maybe 2-3 weeks and put fresh gas in right before then. Was out for about 30 minutes, then at a stop light. I looked down and saw a flashing CEL. Closely listened to the idle which did sound a little 'uneven' for a better word. No horrible rattles outside of the 'usual marbles' sound of the transmission with the clutch out. I quickly turned off into a parking lot and the light just disappeared. Car seemed to run fine. Drove about 3-4 miles back home without the light coming back on. Checked the code with a scanner and came up with p0303 (misfire cylinder 3). Car has 75xx miles, plugs have not been changed to my knowledge (not that they would have been at this low mileage). What's my next step here? Just keep driving and do something if I get another CEL or do something preemptively? Not looking to spend hundreds of dollars on changing plugs/coils, checking the fuel system, etc. if not neccessary. Also don't want to FUBAR my 02 sensors, cats, engine. I'll have to double check, but I'm pretty sure my CPO has already expired (figures). Thanks for any advice.
12-28-2019, 03:04 PM
#2
Rennlist Member
If your plugs have not been changed they need to be. It’s a 4yr item regardless of miles.
also the v
coils have been reved and are better now. You will need the longer screws.
go get new coils and plugs
these cars sound lumpy at idle... watch your durametric if you have one for misfires. You’ll get some at idle normal. It’s under load when it’s. A problem and will trigger cel.
coils and plugs are pretty easy on these.
also the v
coils have been reved and are better now. You will need the longer screws.
go get new coils and plugs
these cars sound lumpy at idle... watch your durametric if you have one for misfires. You’ll get some at idle normal. It’s under load when it’s. A problem and will trigger cel.
coils and plugs are pretty easy on these.
The following users liked this post:
bonehead (12-28-2019)
12-29-2019, 04:21 PM
#3
Rennlist Member
New coils and plugs are easy and cheap to do.
01-05-2020, 10:43 PM
#4
Rennlist Member
Not in my GT3 but just went through this with my C2S. New plugs and coil packs installed.
01-07-2020, 07:14 PM
#6
Rennlist Member
Thread Starter
Just dropped the car off to get the plugs/coils changed along with installing the side bypass pipes. Haven't driven the car since the CEL. Didn't go off again on the way to shop. Hopefully no recurrences after changing out the plugs.