Pontiac g8 gt shift problems
 

My g8 has been having wierd shifting issues, and I want to see if anyone else has shared these experiences or has a clue as to what the issue is. It should be noted the car is bone stock except for a corsa cat back exhaust system.

The car has 26k miles and drove great with no problems. Earlier in summer I was on the highway (cruise set somewhere around 60mph). All of a sudden the car jerked, the rpms rose, the cruise shut off, and the check engine light turned on-then off immediately. I let the car coast and the rpms lowered and the car up-shifted. It happened three times on that week-long trip. Today I went for a ride around town (40-ish mph), and it is happening every mile or so with no cruise on (car jerk, downshift, check engine light flash on/then off, then the car shifting up and returning to normal.

It does not have any issues in manual shift.

I have an extended warranty through Ford till 2014 or 100k miles, but I hate letting other people drive/work on my car. Has this happened to anyone else, or anyone have any clues as to the issue may be?

I am hoping it is electrical and not the transmission going... esp since the car has not been beat on!

Thanks

Sorry to hear about your shifting issue, we have not had anything like that on our 30,000 mile 09 GT.

Just quick things to look at, check all the electrical connectors on the trans, and spray them with electrical cleaner. Loose/corroded connections can cause alot of issues with electronicly controlled automatic's.

I would tell you to check the fluid level, but oh yea you cant, no dip stick. Any signs of it leaking trans fluid?

Our car has not been trouble free, we have had to take it back for the following reasons.

Front control arm bushings, airbag module, drivers door striker worn, recalls.

But nothing that serious. I wonder what sensor can cause it to slip or shift into nuetal like that.

thanks for the reply,

I'll re-check the connectors, I'm hoping this is the issue. There should be no corrosion on the electronics/connections as the car is never driven in winter and rarely in rain.

No leaks whatsoever.

This is the first issue I have had with the g8, so I guess I can't complain. I'm just glad I purchased the extended warranty just in case this turns into a big fiasco. Looks like I'll be taking her into the dealership soon

And here I thought It was my imagination regarding all the little stupid things going wrong with a NEW car.

Mine has a transmission hiccup every once in a while when cold. No engine light or anything, just feels like it's slipping. I've had the dealer check it, they say it's fine. Now it seems like it's whining more than usual. Only 26,000 miles.

Driver's door is giving me "F" body syndrome. Sometimes it unlocks and unlatches, sometimes it doesn't.

Been noticing the steering wanting to wander more.

My remote has disintegrated into a peeling mess.

Grrr!!! I bought a new car to be reliable, not needing to take it in every month for another recall. Sad when my 50 year old cars are better daily drivers with less maintenance needed than a new car.

Sorry for the hi-jack.

Have you checked g8board.com for like issues? Mine had something similar without the cruise shut down and check engine light. Basically just occasional very hard shifts. I'd check the G8 forum if you haven't already.

You might scroll through this and see if you can find reports of similar...if you join (free) you can do an advanced search.

http://www.g8board.com/forums/forumdisplay.php?f=6

The first thing to do is get it scanned to see what code it set and stored. It may not even be a trans issue. You have a warranty use it before you really do need it. I have seen little issues that turn on the SES light be ignored and turn into big ugly issues. Dont wait get it checked out! The only issue I have had with my 09 GT is the fuel cap likes to work it self loose and turn on the SES light. All the GM 6 speed auto's have quirky shifts at times. My 2011 Tahoe is terrible I wish it had the same program as my G8 as the G8 trans works so much better.

I had a 2008 G8 GT that had a simliar issue. There is a tech bulletin about upgrading or re-flashing the ECM in the car. See your GM Dealer about it. I had it done to mine and the shifting of the transmission improved 100%.

http://www.g8board.com/forums/archiv...hp/t-2483.html