power locks.

I have been having this little problem since i purchased the car that deals with the power locks. It is a 1988 park ave, and for some reason when i hit lock, the front driver and passenger side doors will lock, but the back ones won't. So i will manually lock the back doors before i leave the car. Now when i hit unlock, all the doors unlock with no problem. Also, when i first bought the car, the back passenger door would lock sometimes, and sometimes it wouldn't. Now you can that its trying to get some motion, but never really moves more than a few cms, and the back driver door has never locked or seemed to move at all without any manual help.

any ideas on what i can do to get them all working??

You have just described sluggish door lock actuators-- the actuators are weak, or not enough power getting to them (poor connections somewhere in the circuit due to corrosion) or the actual locking mechanism is corroded and needs lubed. So you cvan start by excersizing the lock mechanism first- lock and unlock each one 100 times by hand- then try it- this may help reduce the amount of friction the actuator is up against- and it may work better- if that is still no good- then time to tear open the door- measure the voltage of each actuator as it is activated- if really low- then jumper 12v to the actuator- if this works good- then you know your wiring has bad resistive spots- like a corroded connection etc-- But most likely- the actuator itself is weak- so you can buy new ones- even aftermarket direct fit ones that will solve your problem....