the low down:
stock 116k 12a in an 85 gs. was sitting for the last 3 months til about a week ago when i got her.

the problem:
ok so 95% of the time my car drives great but it does this wierd studder/missing thing sometimes...does it mostly when im either on a steep hill or on a lesser hill but for a long time. what'll happen is its driving fine and then the motor starts studdering. feels like its missing or not getting enough fuel. as a test i tried gettin all over the throttle on a flat rode from a dead stop did great til the top of 3rd and then started doing it. also it does it a lot more frequently the less gas there is in the tank.

my conclusions:
since its an intermittent problem that seems to occur under hard acceleration or on hills im pretty sure it has to do with fuel. possibly sludge in the gas tank or maybe just a dirty fuel filter.

what i want to know is should i just replace the fuel filter? or do you think there's probably some crap in the gastank and if so how would i go about cleaning that crap out? if you want some more info just ask and i'll give the most descriptive answer i can but thats basically whats been goin on. thanks in advance for any help.