98 AW4 tranny problems

Started bout a week ago. Once gas is applied its sluggish off the line almost as if its starting out in 2nd gear. Once I drop the shifter down into 1st it locks up and will not go at all once throttle is applied. Ive hear of replacing the TPS sensor and what not, but could this be a problem on OBD2?? Just hit 90k miles heard of AW4`s last 150k+, what do yall think??? Thanks for any input

AAmco just quoted me $1800-$2000, the computer supposivley scanned a code that said"internal transmission problem". Goin to take the jeep to my old highschool and go talk to the auto teacher, hes got a scan tool, gotta make sure they were tellin me the truth. Anybody had this problem before??

Sounds similar to what happened to mine. For some unknown reason my 2-3 shifter solenoid was getting a short when the tranny woudl heat up. It would do the exact same thing you are describing. It was a $300 part by itself and I didnt know where it was, so I just bought a used tranny from AAA for $300 with the half the miles on my original and put that in. Get it checked out by a full on computer scaner and it should tell you what is exactly wrong with it. There are a bunch of places taht do it for free. Hope taht helps. If you have any questions feel free to ask.