Need to replace heater core on hyundai sonata 2002 gls

Hyundai Sonata 2007 have the two variants which are Sonata GLS and Sonata SE. So check out the engine power of the Hyundai Sonata, which are as follows,

=> The Sonata GLS is powered by a 2.4-liter 4-cylinder engine that makes 162-hp and 164 lb.-ft of torque at 4,250 rpm.

=> The Sonata SE and Limited are powered by a 3.3-liter V6 engine that pumps out 234-hp and 226 lb.-ft of torque at 3,500 rpm.

see if this link helps you out.
sensor camshaft position of hyundai sonata gls 2010 2 4 4 cylinders Google...

The step by step procedure of changing O2 sensor in 2000 Hyundai Sonata GLS can be found in the following link:

http://www.ehow.com/how_7211340_do-sonata-gls-oxygen-sensor_.html

Follow the a/c lines and I am sure you will find it.

You need to call your dealer and provide the VIN#. #s vary on every car - it's a security issue in case someone was to steal your radio.

You first have to drain the radiator, then you diconnect the heater hoses to your heater core .in the engine compartment. Then you remove the cover off the heater core assembly under the passenger side , under the glove box. Then you take straps off the heater core off. and replace . Install every thing you removed previously and refill your radiator and your done.

the vent valve in the tank is not working correctly,you need to ask a dealer if there are any technical service bulletins on this problem

Have you tryed to take off the transmission pan that is directly under the transmission ? It has alot of bolts that would look like the oil pan.

Is the fan working and blowing air but there is now heat?

If there is no heat and air is blowing out check your radiator level. If the engine coolant is too low water will not get to your heater core. Remeber check the radiator level and not just the coolant reservoir. Becareful when working around a hot car. wait til the car cools down to check the level of the coolant in the radiator.

Do you mean the Heater core ? If that is what you mean. It is under the dash just inside where 2 hoses from the inside of the engine compartment go right into the car on the firewall at the back of the engine.Those hoses have to be hot when the engine has been running hot.So be careful. If they are not hot, no hot water is passing through to the heater core.