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How Long Can You Drive With A P0128 Code? How To Fix It

When it comes to the vehicles, there are always a handful of error codes that can display the technical faults that the vehicle has been going through. Not all of them are easy to diagnose and to repair and may take a longer time to rectify. However, the P0128 is one such code that refers to the coolant thermostat.

Usually, it’s better to contact a professional to get things rectified, but if you have a proper guide, it may just be a piece of cake for you. But you need to keep one thing in mind- whenever this code comes up; you need to make sure to get rid of the problem. As a result of this, you can start fixing the problem and get going.

How to Diagnose and Repair P0128?

  • To start the procedure, the first thing that you need to do is to scan your vehicle and then you can check out if the P0128 code is present are not. If you find multiple other error codes being mentioned, you may have to clean them first.
  • The next step you need to do is to check the levels of coolant and also the condition of it. If you find higher levels of rust, the coolant is in poor condition. It needs to be immediately flushed because rust formation can happen at any time. Find out if the coolant level is low. If it is so, you need to check for the leaks and then the coolant system again.

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  • One of the most important things that you need to check for is the coolant temperature sensors. Complete a full scan to know if the sensors are working well or not. The ohm reading will change and it will indicate that the sensors are working fine. If they do not change, you must replace the sensors.
  • Another thing that you need to do is to diagnose the radiator hose and then you can check for the multiple other factors that you need to consider. If the temperature is high, you need to let it out a few times. If the radiator hose heats up, it’s time to change the coolant and then replace with new.

How Long Can You Drive with A P0128 Code?

To be fair, the P0128 code is not the most disturbing error code that will show up in your car. Not just because it is one of the most difficult error codes to show up, but it is also safe to deal with. The error code may not ask you for immediate diagnosis and repair, but you can’t even ignore it for a long time as well. If you start to ignore it for long, it may become a big problem in the future.

The more time you take to fix up the problem, the bigger it becomes and starts to grow. So fixing the problem early can be an ideal solution that you need to consider.

Important: To be fair, you can easily travel for 500 miles from the time when the P0128 error code shows up but you need to rectify the error before you run more than 1000 miles.

What Does P0128 Mean?

Before you get tensed about how the P0128 error code will start affecting you, you must know all about what this code means. Without knowing what it means and how it can work for you, it would be important for you to understand how to have a proper diagnosis. The P0128 describes an error code that acknowledges the coolant of the car engine.

It means that the coolant of the car engine is not getting as warm as it is supposed to be like any other day. So there may be multiple causes because of this and it is the major reason why replacing the coolant and also the other peripherals are important.

How do I fix code P0128 | Causes of Error


1 Coolant Thermostat is stuck open

You need to check if the thermostat is left open for a lot of time. If so, it will always start reading the wrong temperatures. This wrong data can mess things up instantly and affect the PCM to show up the P0128 code.

Thermostat is missing

If there is no thermostat present with the coolant, it could be another reason why this error code is showing up. Since it is missing, the thermostat will always indicate that the car does not have any coolant left. As a result of this, the temperature won’t either come down.

Sensors are faulty

Another common cause of this problem is that the coolant temperature sensor is not working properly. Thus, it can give wrong readings to the PCM at any time initiating to trigger this code.

Radiator Fan

Sometimes when the temperature is high and there is no radiator fan present with the engine, the temperature will never tend to a dropdown. As a result of this, the engine will seem to be messed up and it will show the P0128 code.

Faulty Wiring

Another common reason why there could be a common problem is because of the circuits present inside the engine. If the wiring of the circuit is not working properly, it will not cool down. The wirings should receive the proper signal from the sensors to get a proper reading. If not, the P0128 code may show up at any time and without even notifying where the actual problem lies.

Final Talk

To be fair, the P0128 is not the most difficult of all the codes that you need to consider. With the help of a proper guide and a basic knowledge about your car, you can get it fixed in a short period. However, if the error shows up after a long time, you may not have to repair it immediately as the car will not be stranded. It’s just only that the engine has overheated and now it is getting out of hand. Make sure that you are considering the repairs before 1000 miles to avoid the dangerous situation. Do let us know if this guide was helpful for you or not.

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