SYMPTOMS OF A BAD ECM (ENGINE CONTROL MODULE)
purpose
The purpose of the ECM is to monitor most sensors in your car to calculate ignition timing, air-fuel ratio, and emissions. Some people relate this to the brain of the car. The engine control module also warns you with an engine light if it senses something wrong and gives you a code for diagnostic purposes.
symptoms
engine light
The first symptom of a bad engine control module is having a check engine light on. If the ECM is malfunctioning, it’s going to throw off a code. Here are some codes related to the ECM:
P0600
P0601
P0602
P0603
P0604
P0605
Ensure you can access your car's diagnostic codes by acquiring an OBD2 scanner here.
In some situations, the ECM might be throwing engine sensor codes that don’t even have a problem. You change the brand new sensor, you check the wiring for tears, you check the connections for corrosion, and everything checks to be good but unfortunately, the engine light is still on. This could be due to the internal damage of the ECM. Maybe water got inside and started to cause corrosion or there could have been a shortened side on that specific circuit.
no start
The second symptom of a bad ECM is a no-start. The engine control module monitors important engine sensors in your car, like the crankshaft sensor, mass airflow sensor, and oxygen sensors to make fuel injections and spark decisions. If it’s failing it won’t be able to make the proper commands. All of these factors are super important for your car to start.
engine stalling
The third symptom of a faulty ECM is your engine stalling. You’re driving down the road and your car just gives out and turns off for no reason. The same reason applies here. The engine control module is not giving the proper spark and fuel commands at the perfect time to execute an efficiently running engine.
acceleration loss
The fourth symptom you might be experiencing with your car is a loss of acceleration. The ECM is also responsible for reading the throttle position. If the reading is faulty, it won’t make the right commands, creating an improper air-fuel ratio.
shifting problems
The fifth symptom of a bad ECM is shifting problems. Your car could be making a hard shift when changing gears or maybe you’ll experience a delayed shift. The reason why this could happen is because the ECM communicates the throttle position data to the transmission control module to shift efficiently. If the ECM is sending a faulty reading to the TCM, shifting problems start to occur.
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