Lethal Tendencies

I have a '08 auto LT. When driving between 30 to 45 mph the engine starts surging and the RPMs go up and down about 2000 RPMs. ANyone have any ideas.

XtremeModifier

hmm ...

more details. Shifting gears back/forth (it is an auto...) or is it staying in gear and just surges while remaining in gear? I've found my '08 auto has some speeds/throttle positions where, when driving up hill, it won't find the right gear and will go back and forth every couple seconds or so. I guess GM didn't road-test in West Virginia or the Rockies? lol.

Lethal Tendencies

It does seem to do it more when going up a hill.But very small hills

Lethal Tendencies

Bump,Anyone have this problem?

Lethal Tendencies

well took her in for this problem and they are pulling the tranny

hyperv6

Yep it sounds like a tranny slip if the revs go up.

Not common but it happens.

BDUCK23

mine did the same thing. It would not do it all the time though. It took almost a year and a half for them to get it. I dont remember what it was but I have to go tomorrow to pick it up from the dealer again and i will ask them to check their records. Get it fixed and get rid of it. I am having more electrical problems, wheels are pitting, front doors have rust on them, weather stripping is coming off. All this on a car with 50k, garaged kept, and washed 2 time a week. Switch to Ford. 1997 F-150, 150k with no rust, and have only put $500 into other than oil changes.

gpxsrxracer

My 08 2.4 Automatic is at the dealer as we speak, same issue im sure...does it do it quite often around 36-39 MPH at steady throttle? They cannot figure it out. They have calls into GM right now because they arent sure how to fix it. If and when they fix it I'll post my findings. I'm a Master Certified auto tech(I dont work at a dealer though) and my personal opinion is its quite possibly a lockup converter issue. My HHR would also sometimes surge while sitting at a stoplight as well(not lockup related).

THis is one of MANY issues I have had and still have with this car. Worst investment I have ever made. If I could dump this car I would in a heartbeat but they are worth nothing used, you have to give them away. The issues I have with my car at 36,000 miles shouldnt happen till after 80,000 or more miles. Its absolutely rediculous.

gpxsrxracer

Update: Although I haven't picked up my HHR yet from the dealer as it's now off to the body shop for rust repairs(dont even get me started on this one ) they told me the trans had a bad valve body assembly...as soon as I get it back I'll post up after driving it a couple days and see if that took care of the surging issues or not.

sdafins

Did this fix the problem? I have noticed my 08 2LT, 46k surging very slightly around 38-40 mph, under light load..almost coasting but still maintaining a steady cruise. Give it more gas, and it performs fine.