Car will not shift into overdrive

2011 CHEVROLET AVEO
150,000 MILES • 4 CYL • 2WD • AUTOMATIC
Avatar
STEVEN KEITH
  • MEMBER
  • 1 POST
My valve cover gasket went out filled my spark plug wells with oil. Changed gasket and plugs cleaned wells and the plug rail the same time my gasket went out the car was missing out avid quit shifting into overdrive well the car is running a lot smoother but will still not shift. I am at a loss. Please help.
Oct 28, 2018 at 10:02 AM
Advertisement
Avatar
STRAILER
  • ✓ASE Certified Mechanic
  • 54,832 POSTS
  • ASE Certified Mechanic
Hello,

If the engine cooling system thermostat is stuck open it will not allow the engine to go into closed loop which holds the transmission out of overdrive. Lets run the codes which will confirm the issue. Here is a guide:

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Please run down this guide and report back.

Cheers, Ken

Oct 29, 2018 at 10:40 AM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.