Skip the auto shop - Our mechanics make house calls

Q: Coolant issue engine overheating don't know cause

asked by on

Passenger floor wet. Overheating when driving. No leaking under car.steam coming out vents,smell coolant from vents. Adding water daily. Electrical fan by radiator do turn on. My Ac fan currently doesn't work.im thinking it's heater core. Took of radiator cap when cooled off and noticed black like dirt around the cap on the metal part.

My car has 190000 miles.
My car has an automatic transmission.

A: Hello. You are most likely correct on the h...

Hello. You are most likely correct on the heater core being your issue. This is the component that is located closest to the firewall which will have coolant running to it. The heater core also holds quite a bit of fluid, and would be able to saturate the passenger floorboard if it cracked. Otherwise you would see a leak on the outside of the vehicle more so than inside. You are going to have to drain the coolant to make the repair to the heater core anyway, so do not worry about the gritty coolant at this point. Old coolant can get that way, and you will be flushing the system anyway. Start by diagnosing the extent of damage to the heater core, and most likely replacing it. Then flush the entire cooling system and refill with fresh coolant. Pressure test the system to verify the repair.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Does the fuel pump ground to the pcm on a 2002 grand Prix.

No, the fuel pump ground is in the right door sill on the body. If you check the fuel pump power to the wire that is grey, and it comes from the fuel pump relay in the engine compartment fuse...

Q: Why does my tensioner for my serpentine belt only move about 3" on my 2003 Santa Fe

The tensioner on your vehicle should move more than this. You need to start by checking the drive belt routing. If the belt is not routed right then it will appear that the tensioner is not moving enough. If the...

Q: Power steering leak on a '95 Dodge Ram 2500

You've got to find where the leak is coming from. Power steering pumps put out 1500 PSI or more at times. So, wherever the leak is, you are going to see it squirting out. From there you can figure out...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...