Truck doesn’t overheat but I can see coolant in the overf...

Q: Truck doesn’t overheat but I can see coolant in the overflow steaming and my heater will change from hot to cold all the time.

asked by on October 04, 2017

I have a 2002 Dodge Dakota 4.7l 4x4. I recently replaced the radiator because of a crack in one of the tanks. After that it began to overheat. I since then have replaced the thermostat, fan clutch, both hoses and the cap to try and solve it. So far it has seemed to not get hot over the past few weeks but I still smell coolant from outside the truck. I see no signs of leaks by the radiator and hoses. I checked the overflow and some coolant was steaming from inside, making it the place where the smell of coolant is coming from. Also my heater works great when I’m driving, but when I stopped for a minute my heater started to blow cold even though it was on the hot setting, then as I began driving it got hot again. Then cold one last time as I parked before I turned it off. Still not overheating, sat at normal running temp the entire time. I’m just wondering if it’s not a heater core problem, or possibly a heat gasket. Exhaust sort of smells sweet but I’m not positive.

My car has 164000 miles.
My car has an automatic transmission.

Hi Bryce. Thanks for contacting us today. An overheating issue like you’re describing is often caused by some sort of obstruction in your heater core - especially if the air is cool instead of hot sometimes. However, it is more likely that you’ve got air bubbles trapped in the coolant system. When replacing any cooling system component, it’s vital to correctly bleed the system as recommended by the specific manufacturer. If this is not completed or done right, it can cause the type of overheating you’re experiencing. I think the best thing to do is to have a professional mechanic come to your location and complete an overheating inspection. This will allow them to isolate the root source of your problem, so the right repairs can be made.

Was this answer helpful?

You may have a clogged heater core that may be prohibiting the outer linings of the heater core to get hot. As you know, the heater core is a series of tubes that the coolant runs through that generates the heat from the warm coolant after circulating through the motor. These tubes can occasionally develop a buildup on the inner walls such that when the heater core is "flushed" this buildup on the inner walls of the lines remains and still allows the coolant to flow through the heater core. It is important to note that when the heater core is "flushed" it is possible to get good flow through the heater core while the inside walls of the heater core remain caked with buildup. As a result, the buildup on the inner walls prevents the temperature from rising to its capability due to the insulating effect of this buildup on the inner walls which will prevent the necessary heat transfer to properly heat the inside of the car. I would recommend having an expert from YourMechanic come to your location to diagnose and replace your heater core.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

I have a coolant leak somewhere. I think it is from the reservoir because it is coming from that area, but how do I know?

Look around the reservoir, the reservoir cap, and the hoses to the reservoir and see were the leak is coming from. The leak could be a loose hose clamp, cracked hose, or a cracked reservoir. If you need further assistance...

Problem with fuel system.

Fuel systems are very complex. They include dozens of components such as the pump, filter, lines, regulator, rails and injectors. If you suspect a problem with your fuel system, the best advice is to bring your vehicle to a trained...

Can shaft position sensor all of the outcomes of the problem

Possibilities: 1 - Simply replacing the camshaft sensor will solve your problem. 2 - If it does not, with the age of the vehicle, there can be a break in the wiring harness to the cam sensor. 3 - If...

Related articles

A Buyer’s Guide to the 2012 Dodge Avenger
The The newly redesigned 2012 Dodge Avenger is a really impressive addition to the mid-size sedan market. This model is Dodge’s answer to the likes of the Honda Accord and the Toyota Camry, and while it may not have quite...
The Best Used Cars to Buy If You're a Farmer
If If you're a farmer, you know that what you need isn’t a used car – it’s a used pickup truck. How else are you going to haul around hay, implements, garden produce, fertilizer, and all the other things you...
2012 Jeep Grand Cherokee vs. 2012 Dodge Durango: Which One Should I Buy?
Medium to large SUVs are a fun class of vehicles: plenty large enough for moving people around, but if you really want to get out there in the mud and have some fun, they are still good for that type...