Auto Tranny Grinding??

[napkinthief]

Long story short, I drove about 30 minutes between 25-40 mph on local roads, without heavy acceleration or braking. On my way back home, going about 45 mph a red light came up, so I applied the brakes, and it felt like the brakes locked up, but the wheels did not skid and the car chugged along slowly until it came to a stop. The engine dies and some lights come on as if I put the key in and didnt crank the engine.

So I put it in Park, crank the engine, starts perfect. Shift into drive and the engine dies. This is where I think the tranny comes into play. I did this 3 - 4 times, and finally got it to not stall out when putting it into drive. This kept happening for about 2 miles until I got home, but only when coming to a stop. The car was running smoothly under acceleration or constant speed over 20 mph.

Right before I got to my house, the car was stuck on a hill, and figuring the tranny was gone anyway, I started it from its stalled position in Neutral, revved about 2k and put it in drive. The car caught gear quickly, but made a horrible grinding noise like when you let the clutch go too early. The car has been driving fine the past 2 days.

This is not a dsm question, but if you can fix and diagnose a dsm, you can fix anything. Its a 1992 pontiac grand prix LE. I dont know if I should just sell it before the tranny breaks completely or get it checked and replace what it needs.

 

[Jeff99GS]

Sounds like the Torque converter is staying locked up. The torque converter is suppose to unlock when you press in the brake pedal. Its similar to the action of pressing the clutch IN on a manual trans.

Check all your fluid levels...remeber to do it when the car is running and the trans fluid is warm.

Check for any loose wires or plugs around your brake pedal switches.

In an automatic car the TCU (transmission control unit) gets a signal from a switch on your brake pedal to unlock the torque converter.