hi, I have a 1996 2.5 TL sedan with 90,000 miles.

The 4spd auto transmission will only upshift periodically by itself and I have to let up on the gas pedal a little, then it will shift into the next higher gear and I can then step on the gas to accelerate. If I don’t let up on the gas, it will stay in gear at that RPM.

it is not consistent in which gear or gears it will occur in. For example : it shifted from 1st to 2nd OK. Then I had to let up on gas to shift into 3rd and again let up on gas after accelerating to shift into 4th.

stopped at light and then accelerated and had to let up on gas to shift from 1st to 2nd and shifted ok by itself into 3rd.

what do you recommend to correct and what is the cause?

There are 2 solenoids on the top of the transmission near the firewall just behind the engine. Are these the torque converter lock up solenoids?

where are the 2 shift solenoids located?

Are there smaller filter screens beneath these shift solenoids like the 2nd generation TL transmissions?

any help is appreciated. Thanks.