Guys, need some opinions. I drove my Lancer from 9AM in the morning yesterday till 1AM today. I went from Paranaque to Cubao, Cubao to Dasmarinas, Dasmarinas to Paranaque, Paranaque to Angono, Rizal, from Angono to San Simon, Pampanga, and finally from San Simon, Pampanga, back to Paranaque.

The car only got less than 5 mins. engine turn-off in most of the stops except when I stopped over at Angono (took 30 mins.).

Before leaving Angono, I checked at the tires, body parts, and coolant level. Level is still full in the coolant so I thought things would go well for the remaining trips.

So I then left from Angono to San Simon, but upon arriving at EDSA North the car's temperature gauge went from 1/2 to 3/4... I then slowly went to the rightmost lane, turned my hazards, opened the hood, and checked what could be wrong.. can't find anything (ang dilim pa) except the level of the coolant decreased a bit. So I placed the key to ON in the ignition to check, and the temperature is back to normal (1/2). The temperature went fine for a long while until I'm back en route to Paranaque from San Simon. Bandang Bicutan SLEX na ko nung bigla na namang tumaas ung temp and maya-maya bumalik rin to normal.

So, what could be causing this? Some additional info that may help:

*Car is due for PMS
*Car never got a time to rest from 9am till 1am of more than an hour
*Scent of oil in coming from aircon vents everytime there's a sudden press on the accelerator.