Auto Trans Stuck In 3rd Gear

[JHServin]

Well first off let me just say I am new to this forum, this is my first post so if I do something wrong please guide me in the right direction. Anyways I have a 1990 Nissan 300ZX 2+2 automatic trans and yesterday I was driving around since morning running errands and the car was running great. Later on I went out for another drive at night then after a while I came to a stop at a red light and felt the car didn't downshift, when the light turned green I accelerated and the car felt like when you burn the clutch in a manual trans, lasted about 3-5 seconds but then accelerated. So now when the shifter is in "D" the car starts off in 3rd gear, but selecting gears manually by putting the shifter in "1" lets me start in 1st. I know the gears aren't gone its just not choosing gears automatically anymore. Anyone out there have any idea as to what is causing this? Any help is appreciated, thanks in advance.

[BigTDogg (MA)]

Have you tried the auto transmission diagnostic procedures?

http://www.nicoclub.com/FSM/300zx/

Welcome to the forum!

[JHServin]

No I haven't, thanks for the link I'll try it out as soon as I have time, in the meantime any other suggestions or assumptions as to what is causing this? Any input will be considered as I am willing to try out almost anything at least once.