Skip the auto shop - Our mechanics make house calls

Q: Cooling system

asked by on

Earlier today, I had white smoke coming from under the hood. I stopped and looked to find one of my heater hoses popped off and coolant and leaked out. I brought it to a mechanic and he told me that my thermostat was closed shut and that was creating pressure and thats why it came off. He told me that replacing that thermostat and a plastic piece inside of the hose that cracked would be okay and I should be good to go. Thoughts?

My car has 79000 miles.
My car has an automatic transmission.

A: The thermostat is a commonly known part to ...

The thermostat is a commonly known part to fail causing the coolant to not flow through the radiator properly causing the engine to overheat. The diagnosis sounds about right and is consistent with a thermostat failing. This can be caused by a number of things such as low coolant levels, a faulty thermostat, or a failing coolant fan switch. As you may know the coolant fan switch helps to maintain the proper coolant temperature by turning on and off at specific temperature thresholds.

When this switch is not working properly, this can cause the fans to come on intermittently, all the time or sometimes not at all. When this happens you will notice a temperature spike and drop occasionally as the fan comes on and off. When your thermostat is not working properly or is stuck closed, this will not allow the coolant to properly circulate through the engine, which may cause the engine temperature to fluctuate erratically or in some cases just remain hot. I would suggest having an expert from Your Mechanic come to your home to diagnose your cooling system.

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: Check Engine light on; transmission leak

The coolant temperature sensor is likely what caused your Check Engine light. Sometimes aftermarket manufacturers produce parts of a lesser quality than the OEM. However, this does not mean that all aftermarket manufacturers produce faulty parts. It is harder to...

Q: My car shuts off at 40mph and i have to restart it

Hi there: In many cases when a vehicle simply shuts off while under operation it is caused by a main relay that is failing or a distributor issue. Most professional mechanics will begin to trace this issue by determining if...

Q: Car overheating - 1999 Nissan Sentra

This may be a sign of a faulty coolant fan relay. This relay receives input from the coolant temperature sensor which reads the temperature of the coolant in your radiator. As it reaches a certain temperature, the cooling fan relay...

Related articles

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...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.