mechanic using computer to diagnose car engine issueVehicles manufactured over the past two decades are equipped with three computer systems, including the engine control module (ECM), which monitors engine performance through various sensors. The ECM also works in conjunction with the powertrain control module (PCM) and transmission control module (TCM) systems.

Similar to other car components, the ECM can gradually experience wear and tear, potentially leading to malfunction. These factors can influence your car’s performance, from how functions are monitored to fuel economy. Here’s what you should know.

What Is the ECM?

The ECM routinely processes information from multiple sensors to tune and adjust processes related to combustion, power and efficiency. For three primary functions, the ECM analyzes and manages the fuel-to-air ratio, engine and valve timing, and transmits data to the PCM and TCM. This information assists with braking, traction control and shifting.

Aside from these key functions, the ECM also receives data from sensors related to the air filter, camshaft, crankshaft, radiator and throttle. Ultimately, the ECM ensures your car runs as it should. This differs from older vehicles, which required regular engine tunings and carburetor adjustments. Today, the ECM logs an error code that identifies the issue and eliminates the need to tinker with the engine.

However, identifying these problems requires specialized equipment. The ECM’s operation means that when this system malfunctions, your car no longer operates efficiently or may become undrivable. The ECM may be malfunctioning in response to:

  • An electrical system issue, including a short-circuit, power surge or corroded wiring harness
  • Installing a new starter, which can contribute to a power surge
  • Incorrectly jumping the car
  • A failing battery
  • A malfunctioning sensor

Signs of a Malfunctioning ECM

Your car may be experiencing an ECM complication if you notice one or more of the following issues.

Check Engine Light Comes On

Although this can indicate a number of performance problems, an illuminated check engine light can be a concern in two scenarios:

  • If it seems like nothing is wrong with your car’s operation or performance but the light still comes on, there could be an issue with a sensor or circuit. In this instance, a separate code will indicate the ECM as the source of the issue, rather than a sensor or other system.
  • A damaged sensor is keeping the ECM from receiving accurate data to make optimal performance adjustments.

Engine Stalling

Oftentimes, engine performance indicates a damaged or faulty ECM. As one common sign, the engine stalls or shuts off periodically, without any pattern or warning. This may occur while you’re driving or idling. Secondarily, your engine may seem to operate sluggishly, as if it doesn’t have sufficient power. These factors stem from the information received about timing or air-and-fuel ratio from the sensors.

Your Car Won’t Start

Caused by a stalled engine, your car doesn’t start up efficiently. You may need to start it multiple times or notice the engine cranks but doesn’t power up. These signs also stem from an inaccurate reading of an air-and-fuel ratio and can occur in conjunction with insufficient battery power.

Decreased Fuel Economy

Although multiple factors can contribute to poor fuel economy, an ECM that cannot correctly detect the air-to-fuel ratio often causes your car to burn through more gas. However, understand this problem can be related to issues with the combustion process.

Changes In Acceleration

As the ECM helps your car adjust the throttle, you’re able to smoothly and evenly accelerate when you press down on the gas. A malfunctioning ECM can cause delays in this process, require you to apply more pressure or contribute to sudden acceleration or deceleration.

Issues With Emissions Testing

If you take your vehicle in for emissions testing, the technician will see the vehicle has not been monitoring this process, issues a “not ready” message or delivers incomplete results.
If you’ve noticed any of these warning signs, bring your car to DaSilva’s Auto Body for a diagnostic appointment. Contact us to schedule an appointment today.