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Persistent Overheating

2005 Hyundai Tiburon Keeps Overheating

I live in Washington State and have a 2005 Hyundai Tiburon with less than 110,000 miles. I have had it for 5 years, and have not had any issues with the car until recently (last 2-3 months). My car overheated on me back in May while out running work related errands. I was able to leave it parked downtown while my husband took a break from his job to come pick me up. Since then, it has continued to overheat every time I drive it.

The temperature gauge climbs into, or dangerously close to, the “red Zone” within the first 10 minutes of driving. The first couple of times the car overheated, if I was using the air conditioner, it would start blowing hot air instead of cold air and the air would stay hot. Now when I drive the car with the air conditioner on and it over heats, it continues to blow cold air (if that matters at all).

My super handy husband (a certified motorcycle mechanic) has done the following in an attempt to fix the car:
• Checked coolant levels
• Topped off coolant
• Bled coolant system and added yet more coolant
• Replaced the thermostat
• Replaced the radiator cap
• Water pump was replaced November 2012 (not even a year old yet)

The radiator cap was the most recent fix. It was replaced on a Wednesday evening after testing it and finding that the existing one was not maintaining the proper PSI. The car drove great around town for two whole days without any issues (Thursday & Friday). Saturday, I decided to take it on a longer drive out of town to see if my good luck would hold…it didn’t. I drove a total of 30 miles round trip and my car started overheating after about 20. I limped back into town and barely made it back to our apartment.

My car continues to overheat!! What is going on?! So confused and frustrated. PLEASE HELP!! I’m hesitant about taking it to a mechanic who, my husband is convinced, will just charge me to check all of the things he has already fixed.

@MarissaMiller

Are all of the fans working?

Have you pressure tested the system and verified that there are no leaks?

I have, on numerous occasions, bought defective new parts, INCLUDING THERMOSTATS . . .

In fact, I have a car that started overheating AFTER I installed a new thermostat, which was defective. The store swore up and down that it’s not possible. Nevertheless, the overheating stopped after they exchanged their defective new thermostat for a functional new thermostat . . .

Have you performed a block test? That will give you some idea as to whether you’ve got a blown head gasket

For anyone who doesn’t know what I’m talking about, this is the tool to use

http://www.uview.com/index.cfm?DSP=ProductDetail&ProductID=5122&SubCatID=0&CategoryID=1330&pagepath=Products/Cooling&id=45700

Have you checked that you don’t have a missing airdam?

Have you checked that the condenser isn’t restricted, because of mud, dirt, leaves, bugs, etc. ?

Repeated overheating can kill an engine easily. I hope you can figure this out before it happens too many more times.

Along with the fan question, can you get it to cool down by turning the heat to full blast?

After the engine’s having beenn repeatedly overheated, I would definitely want to see if the cylinders are holding pressure. The gear that db linked you to is great stuff, and it will allow you to do tests other than a cylinder leakdown test, however if the budget is tight there are less expensive (and admittedly less comprehensive) leakdown test kits at the part store…however IMHO it’s critical that you do this at this point. A blown headgasket can be repaired, but the damage grows with every overheat untlil it’s too late.

If you DO find a headgasket problem, know that it may be the cause of teh overheating OR a RESULT. It will still be essential at this point to thoroughly test the rest of the cooling system for leaks and function. If your budget can handle the type of test equipment that db linked you to, that gives you the opportunity to do a good through job. I’m a big advocate of UV dye.

Let us knoow how you make out. We do care.

That tool is reasonably priced

http://www.thetoolwarehouse.net/p-7384-uview-560000.aspx

That is a good price, and definitely a good investment. I was trying to make the point that at this point testing it is a must. Some people tend to not want to spend the money to find out if a particular problem exists, so they just assume “oh well, it probably isn;t that anyway”. Some people only want to spend money on what they KNOW is bad. I’m not suggesting that the OP is that way, but I did want to emphasize the importance of doing the diagnosis.

The fans appear to be working properly and come on when they are supposed to. Turning the heat on high seemed to help some on Saturday, but the gauge would still climb back into the red zone then drop back down to the ½ way mark, climb, drop, climb, drop the whole drive home on Saturday.

Won’t be able to do any testing until next weekend at the earliest as my husband is working all weekend. Luckily, a pickup has been on loan from my parents, so I’m not without a vehicle. I just hate spending so much on gas!