Skip the auto shop - Our mechanics make house calls

Q: Code p0128

asked by on

I have been having an issue with my check engine light sense i bought it. Its throwing code p0128, coolant not getting up to temp. One garage told me it was the thermostat and they replaced it. Another told me it was the cylinder head temp sensor and replaced it. Still getting the code. No idea what it could be. Someone told me it might be the coolant temp sensor but i get a good reading from my scan guage when im driving. On the highway it sits right at 173-175 and doesnt move. If i stop the vehicle and its just sitting idling its gets around 210.

My car has 140000 miles.
My car has an automatic transmission.

Code P0128 is engaged specifically when the engine itself does not get to operating temperature in a specified time period. The only things that can cause this problem is an issue with the thermostat, head temp sensor, and the coolant sensor.

You have replaced the first two, so you should replace the coolant temperature sensor next to see if another sensor may be more sensitive to temperature changes and fix the problem.

If you decide to get this fixed, consider YourMechanic, as a certified technician can come to the vehicles location to accurately diagnose your trouble code in person and suggest an accurate fix. 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: How do you use the song seek menu on the satellite radio?

If your car is equipped with satellite radio, you have access to a number of different features, including one called “song seek”. Essentially, this system allows you to save the names of songs you like and receive notifications when they’re...

Q: Car will not shift out of park

Hi, it could be a failed brake light switch. If you have a faulty brake light switch, the shifter will not move. Locate the brake light switch by the brake pedal and check to see if the rubber bumper is...

Q: My car just shut off while driving nd wont start bsk up dosent even crank over nothing at all turns on

Without additional detail, this would be tough to diagnose, however the fact that it just shut down out of nowhere as you've described suggests that some kind of sensor or relay may have triggered this. I would suggest having an...

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...
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...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.