Drive Accord Honda Forums banner

Car Overheats Going Uphill

26K views 16 replies 9 participants last post by  mtts60 
#1 ·
Hey guys,

Like my title says, my car overheats when going uphill and I'm wondering what it could be. I'm hoping you guys could help :)

When I say "uphill" I don't mean a small hill. I mean when doing a 1 mile (or longer) uphill climb at 5% or steeper climb. Otherwise, my car's temperature gauge doesn't go above the half way mark. It's only been at the half way mark because of the area I live at is so hot with the average temperature for the last month being 110F with highs being 120F or so. I know in winter, the temp gauge didn't budge above 1/4 of the way up. But still, regardless of the environment, it still shouldn't go up all the way up just below the "H" line when going on an uphill climb.

For background reference on coolant system maintenance done:

  • the radiator and lower/upper hoses were replaced around 200k miles
  • Water Pump / Timing belt were replaced around 215k mark

I have noticed that since the water pump / timing belt jobs were done, the reservoir tank was empty so I filled it. This happened twice. I checked the radiator coolant level and it was full to the cap, so I'm presuming there aren't any leaks in the coolant system. I'm thinking there might be a small leak in the reservoir tank, but this shouldn't make it so that my car overheats, right?

What do you guys think?
 
See less See more
#2 ·
If the reservoir keeps going empty, you are losing coolant somewhere. I doubt it is due to a leaky reservoir. The radiator should stay full as long as it can pull coolant from the reservoir whenever the system cools down. Could be your new water pump is leaking or hose connection. Keep looking around the engine when its hot and when its cold.

As for the overheating problem, are both your cooling fans running when it gets hot? Have you ever changed the thermostat? It might not be opening all the way if its old.
 
#3 ·
I know the car isn't leaking coolant from the water pump. The whole reason why the timing belt was changed was because i was leaking coolant from the water pump area to begin with. When my dad replaced the timing belt simply because it was already there to do.

It's been about two weeks since I last checked the reservoir, so I don't know if it's still full or not. I'll check tomorrow again for sure.

I haven't ever changed the thermostat on my car, and I was actually thinking that the thermostat could be the problem. How difficult is it to change out? I know where it's at, but since I've never changed a thermostat that is side mounted. I've only changed thermostats that are top mounted like on most Ford engines.
 
#5 ·
Thermostat sounds likely because your car should be heating up to above 1/4 of the gauge. It should always run around the same temperature, half or just below half, regardless of weather. It might vary a bit but not that extremely.

:banana:Do a pressure test on your cooling system, this will help you find the leak. If you are driving at higher elevations and your AC is on your car can overheat. Turn your heater blower to full on and this will help your car cool down. If you keep driving around like this it is going to cost you.:banana:
Anyone who runs the heater when it's over 100 out is insane dude. I'd rather pull over and wait for a cool down than run the heat at those temps. :dunno:
 
#4 ·
:banana:Do a pressure test on your cooling system, this will help you find the leak. If you are driving at higher elevations and your AC is on your car can overheat. Turn your heater blower to full on and this will help your car cool down. If you keep driving around like this it is going to cost you.:banana:
 
#7 ·
Where can a pressure test get done for a reasonable price?

I live in the low desert. Elevation is 700ft above sea level. Whenever I visit family, I have to leave the desert and go over a very long but gradual increase in elevation. The last two miles of the increase though is roughly a 5% climb out of the desert. These last two miles is where my car is really hurting and the temp climbs up from half to just below the "H" mark.

Thermostat sounds likely because your car should be heating up to above 1/4 of the gauge.
Right, I said in my last post that I think it might be the thermostat as well. I also asked how it gets changed out since it's side mounted and not top mounted. Will I have to drain the coolant entirely, or will just whatever amount is in the hose necessary to drain?

It should always run around the same temperature, half or just below half, regardless of weather. It might vary a bit but not that extremely.
During winter on the REALLY cold days, it will go up to 1/4 of the way up. Right now in the summer, it's usually right at or just a line or two above the half way mark unless doing one of these uphill drives.
 
#8 ·
It could be that your water pump is failing. Try putting it in a lower gear on level ground, and see if the same problem comes about after running it at higher rpms for a few minutes.

There could also be air in the cooling system. Try bleeding the air out of the system. When gradually increasing elevation, air pressure changes, and could cause issues if there is air in the system.
 
#10 ·
I'll have to try the lower gear thing later today.

With air in the cooling system, couldn't i just leave the radiator cap off, drive my car around for a little bit and when the pocket of air reaches the open area of the radiator the pocket of air will just stay there?

When your going uphill are you using AC? Try turning it off and going uphill. I have a corolla that overheats on steep hills when the ac is on.
It never used to do this though. Last year I did plenty of mountain driving with the AC turned on and my car never overheated.
 
#11 ·
#13 ·
The coolant fan spins without issue and so does the AC fan when that is turned on.
 
#15 ·
I've filled the reservoir tank slightly above the "max" line about a month ago and it hasn't gone down since then. I removed the radiator cap and like always, the fluid was right there in my face. So I can say that there aren't any leaks in the coolant system.

I ended up purchasing the thermostat from the my local dealer anyways because I needed to buy something else for my car that i couldn't find at any auto parts store. So, I'll replace that and see what happens afterwards. Hopefully the issue goes away.
 
#16 ·
Sep 6, 2012

I've filled the reservoir tank slightly above the "max" line about a month ago and it hasn't gone down since then. I removed the radiator cap and like always, the fluid was right there in my face. So I can say that there aren't any leaks in the coolant system.

I ended up purchasing the thermostat from the my local dealer anyways because I needed to buy something else for my car that i couldn't find at any auto parts store. So, I'll replace that and see what happens afterwards. Hopefully the issue goes away.
Did the issue go away?
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top