The engine management light in your car won’t appear without a reason – but you won’t always have to worry.
When the EML in your car comes on, you should check for any obvious issues, such as a loose fuel cap.
If replacing this doesn’t fix the problem, then you should have your vehicle checked out soon by a professional mechanic.
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Why Has My Check Engine Light Come On?
Ever wondered why your engine management light suddenly lights up?
Here’s what might be causing the light to come on:
- Blocked DPF
- Ignition system fault
- Contaminated catalytic converter
- Oxygen sensor malfunction
- Mass airflow sensor fault
- Flat battery
- Loose or broken fuel cap
If your car’s EML light is on, then you should book a diagnostic check to ensure that problems like these aren’t impacting your car’s health.
Blocked DPF
If you own a diesel car, then a blocked diesel particulate filter (DPF) can cause both the DPF warning light and EML light to come on.
Your DPF can become blocked if the ‘regeneration’ process needed to clean the filter is not happening when it needs to.
Ignition System Fault
For petrol cars, spark plug issues can cause the engine management light to come on.
Replacing the spark plugs can solve this problem – unless the issue relates to a different related part, such as the coil packs.
Oxygen Sensor Malfunction
Modern cars have sensors in their exhaust systems to monitor the oxygen content of exhaust fumes.
If too much or too little oxygen leaves your car – or there’s a fault with the sensor – the check engine light will come on.
Mass Airflow Sensor Fault
A mass airflow sensor fault can signal that your air filter could be missing, damaged or blocked.
Flat Battery
When your battery is flat, your car’s computer will receive low voltage, and this can trigger an error code in the ECU.
The error code can trigger the check engine light to come on.
Loose or Broken Fuel Cap
If your fuel filler cap is loose, broken or missing, this can cause vapour loss, which can set off the engine management light.
Properly attaching the fuel filler cap can solve the problem, and the EML should turn off after you’ve taken the car for a short drive.
Why Does My Engine Light Come on and Off?
If you’ve noticed that your check engine light keeps coming on and disappearing soon after, you should have your vehicle inspected by a mechanic to get to the bottom of the issue.
Anything from sensor issues to battery problems could be causing the light to flicker on and off.
Even changes in temperature, humidity or fuel quality could be causing engine management alerts which come and go depending on the driving conditions.
What to Do When the Engine Management Light Comes On
If the EML comes on, you should take note of the colour of the light to determine the severity of the issue.
Keep an ear out for any unusual noises or changes in your vehicle’s behaviour – even if the light isn’t red, it may be smart to avoid driving until you’ve had your car checked out by a mechanic.
If the check engine light is red, do not drive the vehicle until the issue is fixed – you should pull over and call your breakdown cover provider if you are on the move when this light comes on.
To keep your car running smoothly, don’t ignore an illuminated engine management light.
Book a diagnostic check to avoid a more costly repair bill down the road.
