i got a 91 v6 3.1 with automatic trans. its having some problems, sometime i have to crank it for about 10 sec. before it will start. then i can hear a little bit of a miss in the motor. then when i drive it the motor starts reving up and down like its trying to die. then when i come to a stop it smooths out but it idles a little high. oh, and it smells like its running very rich, very high emmision smelling.

here is a list of what has been replaced so far.

(by a mechanic)
plugs, wires, distrib. & cap & rotor.

(by me)
pvc valve, airfilter.

 

Sounds like you need to re-set your timing, iac, and then tps, in that order. There are articles on this site that have all the information on how to do each one. Read them all carefully. See what difference that makes, then go from there.