# Car Heater Issue

**URL:** <https://community.cartalk.com/t/car-heater-issue/41127>\
**Category:** Maintenance/Repairs\
**Tags:** hyundai, elantra\
**Created:** [December 22, 2009, 3:40am UTC](https://community.cartalk.com/t/car-heater-issue/41127 "2009-12-22T03:40:03Z")\
**Posts on this page:** 7\
**Page:** 1

<div class="post-metadata">

**Author:** ![ShelleyB](https://avatars.discourse-cdn.com/v4/letter/s/d78d45/32.png) [@ShelleyB](https://community.cartalk.com/u/ShelleyB)\
**Post date:** [December 22, 2009, 3:40am UTC](https://community.cartalk.com/t/car-heater-issue/41127/1 "2009-12-22T03:40:03Z")

</div>

I have a 2005 Hyundai Elantra with arund 73,000 miles on it. When I’m driving my heat works awesome, but as soon as I’m idling at a stop light it goes much colder. If I have been running the car for a longer period of time the heat doesn’t go as cold, but it is still noticeable cooler than when I’m actually driving. What could be casing this???

---

<div class="post-metadata">

**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\
**Post date:** [December 22, 2009, 4:05am UTC](https://community.cartalk.com/t/car-heater-issue/41127/2 "2009-12-22T04:05:46Z")

</div>

This sound like a coolant circulation problem. First thing, check the coolant level to make sure it is not low. After that could be an air bubble in the system or a water pump problem.

---

<div class="post-metadata">

**Author:** ![ShelleyB](https://avatars.discourse-cdn.com/v4/letter/s/d78d45/32.png) [@ShelleyB](https://community.cartalk.com/u/ShelleyB)\
**Post date:** [December 22, 2009, 4:42am UTC](https://community.cartalk.com/t/car-heater-issue/41127/3 "2009-12-22T04:42:13Z")

</div>

Do you think it could be a thermostat issue? Or does this sound like strictly a coolant/water pump issue?

---

<div class="post-metadata">

**Author:** ![nowmaybe](https://avatars.discourse-cdn.com/v4/letter/n/8edcca/32.png) [@nowmaybe](https://community.cartalk.com/u/nowmaybe)\
**Post date:** [December 22, 2009, 4:46am UTC](https://community.cartalk.com/t/car-heater-issue/41127/4 "2009-12-22T04:46:38Z")

</div>

Check the coolant level first. It’s free. I doubt it’s a t’stat issue.

---

<div class="post-metadata">

**Author:** ![geeaea](https://avatars.discourse-cdn.com/v4/letter/g/6f9a4e/32.png) [@geeaea](https://community.cartalk.com/u/geeaea)\
**Post date:** [December 22, 2009, 4:50am UTC](https://community.cartalk.com/t/car-heater-issue/41127/5 "2009-12-22T04:50:03Z")

</div>

No. It sounds like your coolant is low …as was said. If it was a stuck open thermostat, you would lose temp with the ram air. You would have it return idling, if it produced warm/hot air at all.

---

<div class="post-metadata">

**Author:** ![ShelleyB](https://avatars.discourse-cdn.com/v4/letter/s/d78d45/32.png) [@ShelleyB](https://community.cartalk.com/u/ShelleyB)\
**Post date:** [December 22, 2009, 5:06am UTC](https://community.cartalk.com/t/car-heater-issue/41127/6 "2009-12-22T05:06:33Z")

</div>

Okay. So IF the coolant is low, do you think it is most likely the water pump? Or could be the radiator?

---

<div class="post-metadata">

**Author:** ![tardis](https://avatars.discourse-cdn.com/v4/letter/t/f0a364/32.png) [@tardis](https://community.cartalk.com/u/tardis)\
**Post date:** [December 22, 2009, 2:54pm UTC](https://community.cartalk.com/t/car-heater-issue/41127/7 "2009-12-22T14:54:59Z")

</div>

There are many places that coolant could leak from. You don’t want to throw parts at it. You need to examine (or have someone examine) the entire cooling system closely to find any leaks. You/they may have to do a pressure test too.