In a small bowl, combine the canola oil, salt and pepper, to taste.
When the grill is hot, brush the corn with the seasoned oil. Grill on all sides until the corn is charred and tender, about 12 minutes. (Reserve 2 ears for Round 2 Recipe Corn Salsa.)
While the corn is grilling, in a bowl combine the butter, mayonnaise, onion powder, and lime zest.
When the corn is cooked, generously brush on the flavored butter and serve with a wedge of lime.