Happened to me before, pag traffic or idle, medyo mataas yung temp gauge, tapos mainit yung buga ng aircon. Turned out na mahina na yung ikot nung isang rad fan. Akala ko puwede sa carbon brush, pero sealed type pala yung fan ng Sentra Series 3. Ended up buying a surplus fan.

Pa-check mo rin yung radiator mo kung barado. Mura lang naman pa-overhaul, less than P500 (top overhaul ng radiator). Kung pati yung ilalim babaklasin, alam ko P900~ ang singil sa mga rad shops.