T., my last 2 children were out of naps by 18 months old. They are high energy and before they were 2, they just didn't need a recharge. By night time they still didn't think they needed a recharge, but I, of course, knew they needed sleep. I needed it more than they did.
We remained constant with a bedtime routine, and it didn't take long for them to settle down. Once they were asleep,they were really asleep. But, as long as your son isn't showing signs of being irritable during the day due to lack of rest, forget about the nap. My son, occasionally would put himself down for a nap if he needed one.
C. M