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How To Know If My Car Computer Is Bad? 10 Signs To Watch For

How To Know If My Car Computer Is Bad

If you're searching for “how to know if my car computer is bad,” below are the ten most common signs:

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  1. Check engine light illuminating
  2. Poor engine performance
  3. Irregular idling
  4. Difficulty starting
  5. Poor fuel economy
  6. Transmission problems
  7. Inaccurate sensor readings
  8. Stalling or sudden shutdowns
  9. Additional warning messages
  10. Loss of communication with the diagnostic tools

Your vehicle's main computer is a core component that serves as its brain. Sometimes, it might be known as the car computer, or you might hear about it. No one asked about the engine control modules, and in some vehicles, you might hear it's called a powertrain control module.

Regardless of what it's called, this component is critical; without a properly working car computer, your vehicle will not operate as it should, and the systems will not be monitored properly.

Like any other component in your car, the computer is expected to fail; when it fails, you will start noticing some severe symptoms. Still, it's important for you as a car owner to address this issue by identifying the early symptoms of car computer failure.

This article walks you through the ten most common symptoms that could help answer the question, “How do I know if my car computer is bad?”


What is a car computer, and what does it do?

Before we dive into the details of your question, “How do I know if my car computer is bad,” it is critical for you to understand the main and general purpose of this car computer so you can get a sense of how critical it is to address any car computer problems as soon as possible.

According to experts, the car computer, the ECM, or the PCM serves as your car's brain. It controls many important systems, including the emission, ignition, injection system, etc. Without this computer, your car will not know what it's doing, and you'll deal with many issues that might prevent your car from driving the hood.

How To Know If My Car Computer Is Bad

How do I know if my car computer is bad?

If your car computer goes bad, your vehicle will start complaining by showing some symptoms that could help bring your attention to the internal problems. The more you wait for the car problem, the harder it gets for you to fix it and the higher the repair costs.

Therefore, if you notice any of the following ten symptoms, you must consult your mechanic as soon as possible to help address the issue before things get out of hand:

1.      Check engine light illuminating

The first and most common symptom you'll experience when your car suffers from a computer problem is an illuminating check engine. A check engine light will illuminate whenever there is an internal issue related to the engine or any other component, and that's why you must dig deeper and confirm what's going on and whether it's related to the car's computer.

For example, you can use an old scanner that could help you identify any potential or internal errors triggering the check engine light. However, if there is a further complicated problem in the computer, sometimes you might not be able to diagnose the issue, and your mechanic needs to use additional tools to confirm the issue.

2.      Poor engine performance

The engine performance relies heavily on signals from the car computer. For example, it relies completely on fuel injection and ignition timing based on what the computer suggests. Therefore, if the computer fails or is about to fail, you can easily deal with a reduction in engine performance.

However, a reduced engine performance does not necessarily mean a bad computer because it could be linked to another problem period; therefore, once you talk to your mechanic, he should be able to identify any additional diagnosis needed to confirm the issue.

3.      Irregular idling

If you tried idling and realized that the RPM is fluctuating very aggressively, it could be a problem with the computer. If the computer cannot send the right message to the rest of the vehicle, it's not surprising to deal with erratic idle speeds, and things can be out of hand, and your safety might be impacted.

That's why if you're noticing any of this weird irregular idling, you should consult your mechanic as soon as possible and have him diagnose the problem before your safety gets impacted because if this situation happens. You're driving on the highway, you cannot control the vehicle, and things can be even more complicated if you're driving in traffic.

4.      Difficulty starting

Many people who have had problems with their car computer complain about difficulty starting their cars. This is not surprising because the vehicle relies completely on signals from the computer to know when to start the car and to ignite the air-fuel mixture.

Again, difficulty starting can be a very general problem, mostly related to battery issues. Therefore, you cannot assume immediately that it's a complicated computer problem unless you check on the battery and confirm the minor issues are in good shape.

car dashboard

5.      Poor fuel economy

Another problem you might experience if your computer is about to fail is a reduction in fuel economy. It's most likely that the vehicle computer is not sending any signals to the engine, and it seems like the engine is consuming a lot more oxygen than it should, assuming that it's waiting for the signal from the computer to stop.

If you suddenly stop by the gas station more often than before, you should check on the computer because it could be one of the components that need to be updated or fixed.

6.      Transmission problems

The Transmission is another major component in your car; if it suffers from any potential problem, it might be related to the car computer. For example, if you have difficulty switching gears or the gears slip or something like this, although this might be a problem with the Transmission itself, it could be an issue with the computer that needs to be addressed.

If you're driving a vehicle equipped with a manual transmission, you might experience some problems with a clutch every time you try to engage the different gears, and you might realize that your vehicle is not responding the way short.

7.      Inaccurate sensor readings

Most car sensors rely completely on the vehicle computer, and if you find that the sensors are not reading properly, it could be an issue with the car computer. For example, if your dashboard says that the engine is overheating when you have not started the car, then it might be an issue with the gauge itself or something hidden internally. Still, it could also be a problem with the computer.

Since the sensors play a significant role in determining fuel injection timing and other critical tasks in your car, when they do not operate properly, your vehicle will suffer from many problems that might start minor but can get very complicated.

8.      Stalling or sudden shutdowns

What's worse than sudden stalling while driving in the middle of traffic?! Not only is it a critical problem, but it can also mean many safety issues. For example, if you're driving in the middle of traffic or driving on the highway and you notice that your car just stopped suddenly, it can cause many threats and hazards to you and that vehicle driving around you.

How To Know If My Car Computer Is Bad

9.      Additional warning messages

In addition to the check engine light illuminating, you might deal with the other warning lights, like those related to the different systems indicating that your computer is malfunctioning. Some of these errors and warning lights might be easy to read, while others might require additional investigation from your mechanic.

10. Loss of communication with the diagnostic tools

The biggest challenge about dealing with a car computer problem is when you cannot use the Diagnosis tools. For example, suppose you tried using the old scanner but realize it's not translating any of the issues your engines are suffering from. In that case, it might indicate a disconnection between communication and could be a computer problem.

How To Know If My Car Computer Is Bad

How do I know if my car computer is bad? Final Thoughts

Addressing car computer problems is crucial to avoid complications that might cost your car. Therefore, it is important for you as a car owner to understand the main symptoms that could indicate an early car computer failure.

This article explored the ten most common symptoms that could help you identify potential car computer problems and answer the question, “How do you know if my car computer is bad?” If you confirm that the computer is really bad, it might be a good time for you to sell this car, assuming the repair costs are very significant.

If you plan to sell this car and want someone to pick it up without any concerns about the car problems, you can call Cash Cars Buyer at 773-791-4363.

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