Mechanics

OVERHEATING BADLY

2005 Dodge Neon

Engine Cooling problem
2005 Dodge Neon 4 cyl Front Wheel Drive Automatic 97,771 miles

ok I have a 2005 dodge neon 77,000 plus miles. Recently it has been running hot. All the fluid levels are good, but the temperature gage goes to the red and a warning signal comes on. I can turn the heat on and it would come back down. It has done this for a few weeks. Today I started to work, and only got about 10 miles when it happened again, only this time it would not cool down. I ran 20mph back home with the temperature gage near overheating. I popped the hood and you could here the coolant boiling, the reservoir was over full. I turned the car off and went inside for a few hours to let it cool. I went back out and the reservoir was empty. I popped the radiator cap, and could see a rust colored fluid. I started the car to see if the fluids were circulating, after about 5 minutes, it shot about a half gallon of fluid out of the car from where the radiator cap goes before I could turn the engine off. I then refilled the radiator to normal level put the cap back on and headed down the street to test it. Going just 20mph after to blocks the warning signal came on and the temperature gage went all the way to the top. I stopped and checked the level in the reservoir it was empty, with the car running I filled the reservoir to its normal hot level, and headed back home. After I got home, and shut the engine off you could hear it bubbling, but no fluid came out of the reservoir, and it was at the full hot mark.

What is going on with this car, all the hoses look new no wear or damage, the coolant level is normal, why is my car overheating?
Avatar
Dragwiz
June 15, 2009.



After going out a little while later to check the car, the reservoir was empty again after the car cooled back off, so I filled it to the full mark, and went for another test drive. The car did do a little better, it went above the normal operating temperature, but the warning signal did not come on, that was driving at 60mph without air conditioning. On the way back I had the AC on, it did ok until I stopped for a turn then it spiked warning signal came on. Shortly after returning to about 20mph the temp came down and the warning signal stopped, when I arrived back home, the temp was at normal, and I checked the reservoir for coolant level, it was where it was when I filled it last.

I am hoping this was an issue due to low coolant levels, not a blown head gasket? I will post more as I check the car later today.

Tiny
Dragwiz
Jun 15, 2009.
After checking when the car cooled down the reservoir was nearly empty again. No fluids on the ground or around the car. I re-filled the reservoir to it normal level and went on another test drive, with the a/c off the car did not overheat, but it was near the point of over heating, about 3/4 to the max level, where the warning signal comes on. With the a/c on it went to the max range, and the signal sounded once, then it returned to the 3/4 range, when I returned home from this test drive, the reservoir was where it had been when I filled last before the recent test drive.

Could it have been a very low coolant level?

Why does it seem to want to overheat with the AC on?

It did not overheat last summer?

What caused it this year, and what could cause it to do this?

Tiny
Dragwiz
Jun 15, 2009.
Is the electric cooling fan turning on?

The AC takes heat from inside the car and dissipates it in front of the radiator so it's going to overheat easier.

Sounds like a leaking head gasket, but if it runs at normal temperature on the highway, suspect a fan issue.

Caradiodoc

Caradiodoc
Jun 23, 2009.
Yes the cooling fans are turning on. It did ok for about a week driving with no A/C on, the temp gauge stayed close to the 3/4 mark. Hot but not overheating. Yesterday I drove it with the A/C on and the alarm came on while I was going up hill, and the gauge went all the way to the top HOT, however I rolled the windows down, and turned the heat on to get the heat off the engine, and it cooled back down just below the 3/4 mark on the temperature gauge, and I made it home, all the fluid levels were normal. Even the next day when I checked after it cooled down they were normal.

Could it be the thermostat sticking?

A head gasket is a serious repair, and big dollars!

Tiny
Dragwiz
Jun 24, 2009.
Three things come to mind. The first is rotted cooling fins on the radiator. When this happened on my '88 Grand Caravan, it would run hotter than normal at higher than 60 degrees outside temperature and 60 mph. A year later it would run hot on the highway as low as 35 degrees outside temperature. Your car is too new to have this problem, but check for lots of bugs in the cooling fins or other blockage.

The next thing is a worn, broken, or slipping water pump impeller. This is real common on Volkswagens, but I've never heard of it on Chrysler products.

The third thing is the head gasket. Combustion gases entering the cooling system will cause the thermostat to close. Thermostats only respond to hot liquid, not hot air. That's why air bubbles must be bled out before the coolant will circulate. Most repair shops have a " leak sniffer" to test for combustion gases in the cooling system. Air is drawn from the radiator through a special blue liquid. If gases are present, the liquid will turn bright yellow. This test only takes a few minutes and is a dandy place to start.

Caradiodoc

Caradiodoc
Jun 24, 2009.