Hello;
I really like my wife's 2017 CTS. Excellent car. Comfortable, fast and well mannered with great fuel milage to boot. It only has about 16,000 miles on it and has been back to the dealer for the requisite warranty oil changes. I need to take it back to the dealer for some diagnostic work. I do not have a code reader but like to do my own work on all my possessions.
I am experiencing a heavy missfire under load in high gear when torquing up from 1500 rpm. However as soon as throttle is opened up enough to invoke down shift and revs build with turbo boost it disappears. Very consistant and repeatable. I am using mid grade 89 octane fuel. Car only has 16,000 miles or so.
Is this a common problem with these vehicles after breakin? I never noticed this before we got caught in a heavy long distance Florida thunderstorm. It has not gone away even even driven in dry weather. It seems to happen only after warm up. When the engine is cold I have not noticed it yet. Any clues? Thanks

 

what a bunch of braniacs thanks for nothin gals.

 

going to the dealer finally next week.as soon as i learn anything about this situation codes symptoms fixes I will let all of you know. Pretty sad I have to answer my own posts here with over 45 lookie loos.

 

There is a service bulliten issued for what they seem to think the problem is. Apparemtly common amongst these cars is a clutch or torque converter issue which can feel like a misfire. The describe it as a "Stutter". or "Shutter repair" . a three step procedure to solve this issue. 1) change transmission fluid to a higer viscosity according to Shane my Service rep along with filter change. I am to put about 200 miles on the car to see if problem goes away if not then to step 2.

have to get the codes they got when they ran diagnostic.

will keep anyone intersted posted.