ozborcek

Last night I was driving on I-10 and opened it up just a little bit 120mph for a few seconds. Soon after I took the exit the Service Active Handling and Service Traction Control warning came on and I noticed it was running rough. As soon as I parked I read the codes with my scan tool and noticed P0308. (I always have P0420-P0430 due to not having cats).

This morning I looked at the spark plug cables and didn't notice anything loose, although I am not totally sure because the aluminum case holds the wire can be moved easily.

When I started to day I can feel like something shaking under me and when I put in to drive or rear it almost gets worst.

Any feedback would be appreciated,
Thanks

My vett is a 2010 GS with only 13k miles.

ozborcek

*Up date: I started it again and drove around the neighborhood no warning lights came on and was running fine. I decided to run the codes again with my diablo tuner and it showed p0300 instead of p0308 the handheld scanner showed. Looks like I always had the code p0420-p0430-p0300 dealer told me it was because not having cats (I have long tube kooks straight pipe no cats) I still don't get why there is a misfire code and will update again if the service active handling and traction control warnings comes back on.

sevinn

I don't buy the lack of cats giving you the missfire code. You should log each cylinder for misfires individually to see if this is something constant. p0308 meant cyl 8 wasn't firing, while p0300 means the car can't figure out which one is misfiring or maybe a few are intermittently.

ozborcek

I agree I just ordered 8 ACDelco 41-110 Professional Iridium Spark Plugs I think changing them all is a better idea.

I have never changed spark plugs before I have all the tools. Do these spark plugs come set to 40 or do I have to make them? Do I need a torque wrench? is yes what should I set it to? If no how many turns it takes to lock them back in place?

schpenxel

Ideally you'd use a torque wrench. Most don't. Just don't over tighten them.

Having a flexible ratchet and flex spark plug socket helps. Gear wrench makes a nice kit

ozborcek

Update:

I erased the codes using my Diablo tuner. Only the p0420 and p0430 came back due to not having cats. The p0300 (p0308) never came back. I unplugged and replied the 8cylender spark plug cable.
Also the service active handling along with service traction control never came back again. I think it was because of the high speed on the interstate and being bumpy.
The new spark plugs arrived but I am planning to install them if the code comes back again.

KM177122

Glad to hear! Did you ever figure out the route cause of the issue?

ozborcek

Not really it never came back again. I am thinking it was because of the high speeding on a kind bumpy interstate made the car throw off the code.