First, thanks to all for your wealth of knowledge and all of your help. My 95 STS recently started not downshifting. Mainly when the engine is cold, When I take off from a stop the transmission seems to be in 2nd or 3rd gear. I can move the shifter to 1st or 2nd and it doesn't change the gear in the transmission. If I am moving down the road at 50 or 60 and mash the gas to pass, it won't downshift into passing gear. After 15 or 20 miles (or minutes) the problem seems to go away. I can take off from a stop and burn the front tires up, or move the shifter down into 1st or 2nd and the transmission shifts into that gear. It'll also downshift into passing just like it should. I'm thinking (read hoping!!) it's something electronic causing the problem. The car has 109,000 miles, no trouble codes and so far all I have done to fix the problem is change the fluid and filters. Any help would be greatly appreciated.

 

solenoid acting up? but that usually trows a code.
clutches getting worn out? IMO, 109K is not much, unless the car has seen many jack-rabbit off-the-line-starts
or someone uses the transmission to hold a car at uphill stop lights.

i had something close to that once and found out beign a quart low on fluid was doing it.

what did you find when you pull the filter? debri? did you look closely at what came out?
it is important to look when you drop the pan, as any evidence of internal damage is right there to see.
the old transmission fluid can predict the future.

 

Thanks for the reply Stealth. I don't know much about the car. It had 104,000 on it when I bought it.
When I changed the fluid and filters, the fluid was pretty brown and did smell a little burnt. The filters both looked pretty clean. The pan had a very small amount of debris laying in it (maybe a 1/2 of a thimble full). None of it felt "gritty", but I'm not sure what it was. It did seem to be mostly black.
Hope this helps. I love the car, but I'm not sure I love it enough to spend a couple grand on it to get it back in shape. Any other suggestions?

 

I don't know how I did it, but I just realized that I put the wrong year in my post. My cad is a '97 not a 95. Don't know if this makes any difference or not. It doesn't seem like anyone else has seen this problem anyway.