Does any one else having a engine heating up problem since the weather has become colder mine will not heat up even after driving more than 15kms. The guage does not even move and the upper rad hose is luke warm and the lowerrad hose is cold. The dealer says they replaced the thermostat. But it still wont heat up. It is a 2008 accent 1.6l 5spd man.

 

Dealer is most likely correct. Have them fix it under warranty if possible.
Keep us posted.

Otherwise
blockage, pump, low fluid level

 

Remove the radiator cap and double check the coolant level in the radiator when the engine is cold. The dealer may not have bleed all the air out of the system when the thermostat was replaced. The level may be too low to get good flow to the heater core. If it is low, top the radiator off with a mix of 50 to 60 percent antifreeze.

If its below 0 F (-20 C?), it sometimes help to place a cardboard air dam on the front side of the radiator. Cover about 1/2 to 2/3 of the radiator surface. This is the same idea as the canvas air dams you see truckers use on the front of semi's in cold weather. Since this is a manual, you shouldn't need to worry about blocking the transmission oil cooler. Remember to remove the cardboard when the weather warms up.