hard to start on 1993 Mazda B2600

pickup is hard to start on rainy days. changed rotor and distributor cap but no help. what next?

1 answer
Really the whole tune-up should include the wires, plugs cap and rotor as well as the air filer and fuel filter and a timing re-set. If those are in really good shape, then check the coil, make sure it is really strong and then check the codes for a sensor being out of range.