spark/engine hesitation on 1991 Nissan 240SX

hi my nissan 4 cylinder auto trans truck has a skip when driving the highway at 60 MPH not all the time. once in a while like the spark stops or something and then carries on not again for a long time or a short time. Not a comsistant thing.Noticable when it happens.

Asked by for the 1991 Nissan 240SX
1 answer 1 comment
Really need to carefully inspect all of your tune up parts i.e. wires, plugs, car, rotor as well as your fuel filter and air filter. I never let these go for more than 30k and the air filter I replace every year.
Thanks for your prompt reply. I put new plugs in. the cap all 4 contacts were really corroded up i had to scrap the white hard carbon off them it did run better. Maybe the cap needs replacing otherwise it sits and idles nicely. the rpms flictuate up and down a bit but thats all.