Nissan Repair: my 90 max is missing when idleing/running, optical pickup, rotor

Question
My '90 max is not idleing/running to manuf: spec. change plugs and wires but cannot seem to find problem. can any-one help me? thank you

Answer
crb,

The distributor is probably going out and that is causing the intermittent miss when at idle and while running.  Take the distributor a part and look for the presence of oil on the optical pickup.  This is under the cover that is under the rotor post.  To take the cover off remove the cap and rotor and then the rotor post and cover.  There is scres in the middle of the rotor post and then there are two screws that hold the cover.  Be sure to note the location of the rotor post so you can put it together properly when done.  If there is oil on the optics then get a rebuilt unit.