After many months and many remedies I finally got to the root cause of my shifting maladies. It’s an electrical connector behind the glove compartment. To make a long story short, I took my HHR to a GM dealership and the tech told me what it was and told me he cleaned and applied dielectric grease to the pins in the connector and said if it happened again to bring it back so he could install a new connector. Well, it started again 6 months later so I took it back and dropped it off only to be told that GM discontinued that connector and he is at a loss where to find one. He said he searched the internet because GM made a kit especially for that with a new connector and pins but he can’t find one now and said it’s been out of production for years. Any leads would be appreciated.

 

the first thing that comes to mind...
if this connector is no longer produced - there is definitely a replacement for it for similar purposes (not necessarily GM, here your hands are untied).
You buy any approximately suitable connector and a mating part for it, ask an electrician to replace both parts. Double work, double money, but 100% result.

By the way, is there a picture? Send it to take a look.

 

A 2006 1LT 2.2 automatic transmission, I don’t know of any transmission connectors behind the glove box. The HVAC box resides there with the blower fan and the cabin air filter.