Hey guys,

I have been doing some searching and read a few things but wanted to know if there was some new info out there.

I have a 2010 SS with 12k on it. I just spent this last week at the scca autocross nationals. Car ran great no issues at all. Now on the way home we hit a lot of rain, Nebraska to Wisconsin was all rain lol.

I filled up in Iowa with 92 octane and set off for home. Car ran fine at highway speeds but sometimes I hit some red lights and the car would sputter in 2nd. I got to my road in Wisconsin and hit it again and right at 4k it would sputter fall then kick back in. When I got home I noticed a rotten egg smell you get from cats sometimes. I let the car run for a bit thinking I had bad gas and took it out again.

Didn't have the issue one testing it around town. Then went to the local mobil to get some good 93 octane and the car felt even better. Not issues at all.

Like I said I did some searching and checked over the coils, plugs and connections with no issues. Any help would be nice. I'll keep everyone updated as I drive it tomorrow.

 

clogged cat? id say bad gas though.

 

Is your car stock? I would check if it's knocking or what the fuel trims are with your RPD. Could have been bad gas though.

 

Yea sorry forgot that part. The car is bone stock. I was looking the RPD when I Hit hthe sputter in town and everything seemed normal. Fuel psi was good boost was normal... Just odd.

 

Dreaded EVAP issues is what it sounds like to me?

Hard to try and help diagnose but that seems to be the most prevalent problem with "sputtering" issues

 

Evap issues? Didn't see any of those in a search. What are they?

 

Alright after going for some long driving today the car feels great. No issues.

Overall my guess is the switching from one gas to the other then to another. Wisconsin we still have 93 for the most part. Iowa and Nebraska had 91 and on the way back home some place had 92. I bet it just confused the crap out of te ecu.

 

sounds like some skewed fuel trims. just keep an eye on it for the next tank of gas or 2.

 

I had a similar sputtering past 4k RPMs under throttle.

It happened when the car had less than 3k on the odometer though. It ALWAYS happened during/after driving for two or more hours. It hasn't happened since so I chalked it up to sustained RPMs and let it go... *shrugs* That was pre-GMS1, too.

 

probably not this, but just a though, when i was logging someones car and they were having signs or sustained knock the motor killed power to protectthe motor. Maybe you got some bad gas and tis happened, idk just throwing that out there if it onl happened once.