It seems to work when it wants to. Sometimes it accelerates without me prompting it. It also sometimes decelerates again, all on its own.

Anyone have any ideas?

 

losing vacuum. check vacuum hoses and vacuum ball/reservoir. see some recent threads regarding wild/erratic/haunted vents

 

on my '94 the vacuum ball was behind the panel below the passenger headlight... you can access that ball by removing that panel with a screwdriver and 1 screw to the left and below the headlight... then pull off the panel from the front... check for rotted hoses going to that hollow ball

 

Thanks for the info guys. I'll check it out and see what's happening there.