2003 Elantra - Overheating

I started having a problem a couple of months ago. My air conditioner worked fine but at redlights or upon slowing down, the temp gauge would start to go up and the air would stop working. I had a friend look at it. He said both fans were working and it seemed like something (i cannot remember what) was not engaging at lower RPMs. He said I may just need some oil (installed like refrigerant). He told me to put car in Neutral at redlights and rev the engine to keep it from overheating. I did this successfully. Each time I would stop, I did this and it worked like a charm. Well, the last couple of days, the temp gauge has been redlining. I put coolant in the radiator but it hasn't help. I know very little about cars and don't know anyone else that does either but I am hoping someone here can help me diagnose. I popped the hood last night as soon as I stopped and the coolant was boiling. The upper radiator hose was really hot. I looked up under the space where the radiator hose connects to the engine and saw lots of hard, crusty whitish rock like stuff around the hose connection to the engine. I could chip this off relatively easily. I am not sure what this is. The hose looked like it had a good connection. I know I need to take it in to be serviced but to be honest, I am single with a kid in college and I just can't afford to be taken advantage of...I am scared this is what will happen. If I had some idea of what it could be, I would feel better about dealing with a service department. I bought a new Thermostat (after hearing how easy these were to change out) but I looked and could not find where this would go. If it could be the Thermostat, can someone tell me where this is located? I appreciate any and all advice. Thanks, Sheila

I seriously think you should seek help on a Elantra oriented forum :

elantraxd.com

if you search the forum you'll find LOTS of answers about thermostat;

http://www.elantraxd.com/forums/showthread.php?t=24995
http://www.elantraxd.com/forums/showthread.php?t=18400
http://www.elantraxd.com/forums/showthread.php?t=15880


and here is a DIY thermostat change, not for the Elantra but the thermostat location is nearly the same (it's in the same area);
http://jalopnik.com/cars/car-care/and-you-will-know-us-by-the-trail-of-parts-replace-a-thermostat-240953.php

This forum is not extremelly crowded with Hyundai enthousiasts as we get laugh at a lot.

You rock, J!

I didn't realize I would be the subject of other's ridicule for having an Elantra :( I mean, I know it's not the coolest car in the world but it has been a great car up until now.

Well Hyundai in general have a bad rep. but I never had bigger problems than with any other car I had, either domestic or imported, Hyundai's car are really the best bang for the buck you can find out there and they are fun to drive! :)

Good luck with your overheating problem! :)

I started having a problem a couple of months ago. My air conditioner worked fine but at redlights or upon slowing down, the temp gauge would start to go up and the air would stop working. I had a friend look at it. He said both fans were working and it seemed like something (i cannot remember what) was not engaging at lower RPMs. He said I may just need some oil (installed like refrigerant). He told me to put car in Neutral at redlights and rev the engine to keep it from overheating. I did this successfully. Each time I would stop, I did this and it worked like a charm. Well, the last couple of days, the temp gauge has been redlining. I put coolant in the radiator but it hasn't help. I know very little about cars and don't know anyone else that does either but I am hoping someone here can help me diagnose. I popped the hood last night as soon as I stopped and the coolant was boiling. The upper radiator hose was really hot. I looked up under the space where the radiator hose connects to the engine and saw lots of hard, crusty whitish rock like stuff around the hose connection to the engine. I could chip this off relatively easily. I am not sure what this is. The hose looked like it had a good connection. I know I need to take it in to be serviced but to be honest, I am single with a kid in college and I just can't afford to be taken advantage of...I am scared this is what will happen. If I had some idea of what it could be, I would feel better about dealing with a service department. I bought a new Thermostat (after hearing how easy these were to change out) but I looked and could not find where this would go. If it could be the Thermostat, can someone tell me where this is located? I appreciate any and all advice. Thanks, Sheila

Sheila, I am experiencing exactly the same problem in the same manner as you described, did you ever find out what the solution was? Please email me at [email protected] ([email protected]), thanks jim.

Hi, i own a 2005 elantra. I am experiencing exactly the same problem just as you described even the white stuff on the hose connection, have you found a solution, please let me know. Jim at [email protected]

Go to elantraxd.com.....ask for help...they will help you!

I experienced overheating problems with my 2001 Elantra. I checked the following systems, all of which were operational: fan motors on the radiator, water pump, belt tension, fluid level, overflow reservoir, crankcase oil level, and the radiator cap. The thermostat seemed to be working as judged by the rate of temperature rise from a cold start. The car when started would warm up to its normal operating range over a few minutes, the thermostat would appear to open and maintain the normal operating temperature, the top radiator hose would be hot once the thermostat opened, and everything looked OK. After about 10 minutes of operation the temperature would start to rise and would continue to rise to the highest gauge point. I would shut the engine off and observe the flow of collant from the radiator into the overflow reservoir. I finally removed the thermostat housing after the engine cooled down and found that the thermostat had broken into two peices. It had separated where the cone shaped valve attached to the main thermostat shaft. I replaced the thermostat, put new antifreeze into the system, and refilled the overflow reservoir. Upon starting the engine and letting it run for 7-8 minutes, I went for a test drive and the problem was solved.
This was a pesky problem because I had never seen the kind of symptoms observed before and I have been a shade tree mechanic for over 50 years. Over the years I have diagnosed and changed a lot of thermostats. I hope that this will be helpful to those who may find similar problems with their Elantras. I suspect that Sonata owners could also experience the kind of thermostat failures that I found with my Elantra.

i hope you never blowen a head gasket it only takes over heating one time then your screwed. but about your thermo it should be right at the end of your top rad hose.