just bought a '95 z-28 and trying to pinpoint a problem i'm having . car has erratic idle . also it stumbles when you step on it , like it is misfiring . also at idle the oil presure is erratic , going up and down with the the idle rpm's .i'm thinking maybe plugs , wires , but i am reading about the "optispark" . what is this and where is it located . could this be the root of my problem ? thanks in ADVANCE GUYS , _v_

 

Opti spark could be the problem, i'd also look into getting all fluids changed if you just bought the car, and run some FI cleaner through the system. Just my 2 cents, but also do some research on best plugs, most people on here say NGK's are the best, i'm looking at getting them myself. So who knows. Good Luck!