Hi, I have a 2001 Elantra. When i come to a stop at a stoplight the heater blows cold air but when I start back up it starts blowing warm air again. Any help would be greatly appreciated!

 

Hi there! Well, it sounds like you have a vaccum door problem in the climate control system. This means the air flow door behind the dashboard is not staying open when you stop due to loss of pressure in the vac hose to keep it open. Thats why when you accelerate, you are creating more pressure in the line and so the door opens again. This was a very common problem on many Ford cars who used a similar design. This is just an educated guess of course because thats what was wrong with my car. Does the air switch to the vents or defrost when you stop or does it not come out at all?

 

it is the thermostat. i've had an '03 and an '04 elantra and had the same problem in both of them. the car was under warranty still and they replaced the thermostat and the problem was gone. good luck.

 

the 01 elantra doesn't use vacuum to control the vent doors and if there was a problem with the thermostat then the car would take a long time to warm up or overheat depending on the condition it is stuck in. stuck open would take a long time to heat up/get warm, stuck closed would cause the car to overheat. what that seems as if the coolant is low in the car so there isn't enough coolant in the system so when the car is driving the water pump pumps coolant through the system faster therefore moving the hot water in the heater core to provide heat. check the basics first. make sure you have coolant in the system. hope it helps

 

I have had the same problem with my 2003 Elantra! Actually about a year ago, the heater wasn't working properly and the car was also overheating- so I got the thermostat replaced. However, once again this winter, having the same issues with the heater. WhenI give it gas, it warms up and when I break or slow down at all, it's ice cold again. I will check the coolant, but I'm really hoping it isn't the thermastat again since I only replaced it a year ago.

 

This condition is normal

Due to flow issue port on the heater core inlets & outlets also thermostatports size. Hyundai is aware of the issue. They have tried different size thermostathousing, No help

 

This condition is not normal. I have the same problem on my 2004 Elantra. I never had any problem for the first 8 years. The problem just started this year. I have yet to figure out what the problem is. I will report back when I find the problem and the solution to it.

Schniz

 

I have an 06' elantra with 118,000 miles on it. In the last thousand miles, I've noticed that the heat works occasionally. When I start the car to heat up in the morning, the car warms up but the heat doesn't blow. Once I begin driving, the heat will warm up but will go back and forth from heat to cold. Most of the posts I've seen say to change the Thermostat but I'm not sure what to do. I haven't noticed the car overheating at all but I will keep a look out. It may not be overheating because its so cold outside. Please advise with the best course of action.

 

I have a 2008 Elentra and my heat only comes out of the chest area. The dial turns to all positions but is unable to properly hook into one position. any suggestions?

 

The heat in the vehicle is generated from the engine. Check hoses for leaks, check water pump weep hole for leaks, check the belt, check the fluid level, and/or flush the system for any debris. Sometime the hose will break down from the inside and show no sign of wear on the outside. Pieces of rubber will keep the thermostat from operating correctly or restrict the flow of antifreeze to the heater core. Good luck.