Skip the auto shop - Our mechanics make house calls

Q: thermastat stuck removed now the car isnt regestering hot but can hear boiling from motor

asked by on

Thermastat removed no leaks not reg hot but can hear boiling from motor rad not smoking ac used to make. Knocking sound now that has stopped an not working at all

My car has 1700000 miles.

A: First off, you need a working thermostat in...

First off, you need a working thermostat in the car for it to function properly. If you removed the thermostat to fix an overheating problem, you will need to install a new one and begin the process of diagnosing the problem.

You state you hear boiling from motor. Hearing boiling or the rushing of water is usually due to the cooling system being low or there is an obstruction in the system.

The first thing that needs to happen is the installation of a new thermostat and to make sure the cooling system is full. To do this, once the thermostat is installed, fill the system, run the motor until the thermostat opens with the radiator cap off. You will know the thermostat is open when the hose attached to the thermostat housing gets hot. I recommend this tool for running a car with the radiator cap off.

It allows the coolant to expand as the car warms up. Once the thermostat opens, the level in this large funnel will drop and you will need to add more coolant quickly. Once the level stays constant and the thermostat is open, you can begin to diagnose what I assume is an overheating issue.

If you did install a thermostat and you hear what you describe as a boiling, you need to make sure the cooling system doesn’t have any bubbles in it. You do this by following the procedure with the tool I recommended. This will allow any air in the system to eventually escape out the radiator neck. This can take awhile, so don’t be alarmed if this bleeding takes as long as an hour.

This is just a place to begin. I am not sure exactly what is going on with your car from your description. I’d recommend getting your vehicle looked at by a qualified technician who can diagnose your overheating issue and other symptoms you’ve described. Once this is done, an accurate repair can be made to get your car running normally again.

Good luck.

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・Fair and transparent pricing

Get a quote

What others are asking

Q: Temperature guage fluctuates between mid temp (normal running) and cold at higher speeds

This may cause other engine problems relating to the engine not warming up properly to run at normal operating temperature. There are many other systems that run based upon engine temperature and coolant temperature. Fuel injection and timing for example,...

Q: Car is making a knocking noise. 2006 Toyota Corolla

Hi - your engine could be knocking from bad fuel, ignition problems or bad bearings. Check your engine oil level first - a low oil level could be the most damaging. If the Check Engine light is illuminated, have the...

Q: Vehicle not starting.

It sounds like your Tacoma may have a low battery, a failing battery cable, or a bad starter. If the engine will only crank partially over then there is either not enough power getting to the starter or the starter...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...