Automotive News

What Is the Engine Control Unit and How Can I Tell If I Have a Faulty ECU?

The Engine Control Unit (ECU) is also called the Engine Control Module (ECM), and if you hear people talking about the “main computer” in your automobile, this is it. This module processes information sent to it from engine sensors so it can regulate your engine’s performance by making adjustments to the air/fuel mixture, fuel usage, and combustion sparks. If you drive a new car, it controls even more than that. How can you tell if your ECU is faulty? Lucas Auto Care lists the symptoms of a bad ECU below.

Engine Lags or Surges

Because the ECU controls your engine’s timing and fuel usage, you might notice engine performance issues such as lagging or surging in the module is going bad. For example, if your engine isn’t getting enough fuel because the faulty ECU has thrown off the air/fuel mixture, your vehicle will lag or stutter when you step on the accelerator. Too much fuel can make your engine surge and reduce your fuel economy. The ECU can throw off your engine’s timing, as well.

Engine Misfires and Stalls

If the above issues are significant, your engine might misfire and/or stall. The ECU controls the order in which the spark plugs fire, for example, and if that order is compromised by a faulty engine control unit, you’ll end up with misfiring plugs. You may find your engine idling roughly, sputtering as it tries to pick up speed, or even stalling while you’re stopped and idling or while you’re in motion. How much fuel is sent through the engine can also affect these performance issues.

Your Car Won’t Start

The engine control module does what its name suggests: It controls the engine. If the ECM has died completely, you won’t be able to start your car. Your engine could cut while you’re driving, as well, if the ECU malfunctions. Once you’ve coasted to a stop, you won’t be able to get your automobile started again. It’s a good idea to get your engine control module tested at the first sign of trouble. If there’s a problem, we can replace it before you end up with a dead car.

Check Engine Light Alert

How can you tell if your ECU is having problems? Usually, the check engine light will come on at the first sign of trouble. This catch-all dashboard warning light is controlled by the ECU, and it will turn on if the ECU starts to malfunction. This malfunction is generally a false alarm, i.e. the engine control unit turned on the check engine because it thinks another engine part or system is having problems. False check engine warnings are usually attributed to an ECU or electrical problem.

Call or stop by Lucas Auto Care today if you think your automobile’s ECU is malfunctioning. You can count on our European auto repair shop in Cypress, TX, to find the problem and fix it.

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