I've read a lot online about this but still cannot determine whether to junk the Jimmy (130,000 miles) or not. The car isn't worth replacing the tranny. But I'd still like to keep it since it plows my drive in the winter.

Brought the car home one day and tried to back up. Nothing. Checked the fluid which was a little low so I put a quart in and still nothing. The shift cable is a year old and it still shifts as it should when I put it in the selected gears. I took it for a test drive and it shifts through all the forward gears as it should. It's a little slow going into Drive though. I read somewhere that if the problem is the sun-thing the tranny won't shift into 2nd either. But it does.

Now I have noticed the temp guage never goes up to operating temperature any more though I get plenty of hot air in the cab. Coolant level is ok. Could a bad temp sensor throw the PCM off and cause this?