I have a 1988 nissan pathfinder 3.0L V6 with a starting problem, I have replaced the carb, heatscreen,and had the vehicle start easily. It ran like a dream only problem is once it gets warm it won't start again and I get a loud clicking noise coming from the relay switches on the passengerside fender, I am wondering if there is a way to check the functionality of the relay switches?

. Clean battery cables/terminals and fully charge battery.

Relays often "chatter," due to a drained battery or bad ECM.