A lit-up engine management light (or EML) on your car’s dashboard means that the on-board sensors have detected a problem. 

Unlike other dashboard warning lights, the EML won’t alert you to a specific problem – it comes on to let you know that there is an issue with the engine, emissions system or exhaust. 

Noticed an illuminated EML in your car? In this blog, we cover what the EML means, what could be causing it to come on, and what you should do next... 

 

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What Does the EML in My Car Mean?

The engine management light in your car is an engine-shaped symbol on your car’s dashboard. 

It is triggered by the onboard computer system if an engine-related issue is detected. 

It does not indicate a specific problem like other warning lights do but lets you know that something is wrong with your car. 

The EML usually lights up when you start the vehicle and should switch off after a few seconds. 

If the light stays on or starts flashing, that means there could be a problem with the engine or another related part. 

Some EML problems are far more serious than others, as indicated by the type of light that comes on. 

 

Steady Amber Engine Management Light

An amber engine management light.

A steady amber engine management light - which could look yellow or orange - usually indicates that there is an issue with emissions.

This is the least severe type of check engine light you may see.

If a yellow engine management light comes on, you should be able to finish your journey - provided the vehicle isn't experiencing a lack of power. 

Even so, you should book a diagnostic check with a mechanic as soon as you reach your destination. 

 

Flashing Amber Engine Management Light

A flashing engine management light.

A flashing amber EML is more serious than a steady amber light.

This type of engine management light means that there may be a critical problem with the catalytic converter or another vital component.

You should stop driving right away and contact a mechanic.

 

Steady Red Engine Management Light

A red engine management light.

A steady red engine management light means that there is a critical issue with your car.

You should stop driving if you see a red engine management light and call your breakdown cover provider right away.

 

Why Has My Engine Management Light Come On?

The engine management light can come on for a wide range of reasons and bring anxiety with it when it does. 

Not to worry, though – the EML is there to give you a chance to fix potential issues with your car!

Whilst it can be difficult to determine the exact cause without a mechanic, here are some of the most likely reasons why your car's EML is illuminated:

  • A blocked DPF
  • An ignition system fault
  • A contaminated catalytic converter
  • An oxygen sensor malfunction
  • A mass airflow sensor fault

 

Blocked Diesel Particulate Filter (DPF)

Most modern diesel cars have a diesel particulate filter (DPF) warning light.

When the filter becomes blocked, the EML is likely to come on, too.

If the DPF does not regenerate when it needs to – be this active or passive regeneration – then you may need to book in with a professional mechanic.

You may wish to book a DPF clean if the problem is not too severe to try and prevent the diesel particulate filter from becoming blocked. 

 

Ignition System Fault

In a petrol car, a flashing engine management light can indicate there's a problem with the spark plugs or coils.

Petrol-powered cars rely on the ignition system to run the engine, and the car can misfire and lose performance if there is an ignition system fault.

If the spark plugs or coils get old or develop a fault, they will struggle to provide the spark that helps fuel and air combust within the engine.

This can make it hard to start the vehicle and will cause a jerky drive or occasional dips in power whilst driving.

 

Contaminated Catalytic Converter

You should have a contaminated catalytic converter looked at immediately.

The catalytic converter keeps exhaust emissions as clean as possible.

If the catalytic converter fails, then this can cause the EML on your car to come on.

Not to mention that any issue or damage can lead to a very expensive repair if left to deteriorate.

 

Oxygen Sensor Malfunction

Modern cars have sensors in their exhaust systems to monitor the oxygen content of exhaust fumes.

These ensure that your car is as efficient and environmentally friendly as possible.

If too much or too little oxygen leaves your car, or there is a fault with the sensor, the check engine light will come on.

Not enough oxygen indicates that your fuel is burning too rich, whilst too much indicates that your fuel is running too lean.

 

Mass Airflow Sensor Fault

A mass airflow sensor fault can signal that your air filter could be missing, damaged or blocked.

Without the data from this sensor, your engine control unit (ECU) will assume that the engine is getting no air at all and will trigger the EML.

This will protect the engine from overheating and causing serious damage.

You may experience rough idling or jerky acceleration if the engine isn’t burning enough oxygen during combustion.

Your car’s air filter should be changed every couple of years.

 

Illuminated EML? Here's What to Do Next...

Has your car’s EML come on? 

The underlying issue needs to be diagnosed and fixed by a professional mechanic during a diagnostic check.

It is especially important that you book a diagnostic test if the EML is flashing or has been on for a while, or if you’ve noticed changes in your vehicle’s performance. 

Even if the light isn’t red, it’s still a good idea to stop driving until you’ve had the car checked by a mechanic. 

If the check engine light is red, do not drive until the problem is fixed – you should pull over and call your breakdown cover provider if you are driving when this light comes on. 

The EML is unlikely to reset itself, so you need to take your car to a garage so that the issue can be diagnosed. 

Once a mechanic has fixed the problem, the EML should turn off automatically. 

If the light comes back on even after the issue has been fixed, you should book back in with the garage. 

Your EML is telling you something important, and finding a fix early can save you money in the long run. 

Not to mention that an illuminated EML will result in MOT failure – so it’s best that you book a diagnostic check ahead of an upcoming test to give your car the best chance of passing. 

Booking a diagnostic check now could prevent extensive engine damage later down the line – so why wait to find the right solution for your car? 

 

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Frequently asked questions

Is the Check Engine Light the Same as the EML?

Yes, the engine management light is also known as the ‘check engine light’ or ‘engine warning light’.

Will My Car’s EML Reset Itself?

Your EML can sometimes go away on its own, if the cause is something small like a loose fuel cap that needs tightening.

If your car’s ECU continues to detect a fault, though, then the EML will stay on – in which case booking a professional diagnostic check can help to pinpoint the underlying issue.

You can try to reset the light yourself by parking in a safe place and restarting the engine after 2 minutes – if the light stays on, you will need to take your car to a garage to have the issue fixed.

If you notice that the EML turns off and on intermittently, then the sensor may only be detecting the fault at certain times – you should take your car to a garage to fix the problem.

What Will Fix a Check Engine Light Issue?

Depending on the underlying issue, the fix could involve, replacing, tightening, cleaning or recharging a specific part.

Whatever the cause, it’s best to address the problem as soon as possible, so that you can save on repair costs in the long run.

Can I Drive When the EML is on?

Generally speaking, as long as there are no issues with the engine and the light is only a solid amber, you should be able to keep driving to your destination.

That being said, you should have your car checked by a mechanic as soon as possible to avoid causing additional damage to your vehicle.

If you notice any other warning signs, such as unusual noises or a dip in performance, you should pull over when it is safe to do so, switch off the engine and call a breakdown provider.

You should likewise pull over if you notice a red or flashing EML, as this can indicate that a more serious problem is present.

How Long Can You Drive When the EML is on?

Regardless of the colour of the light, you should drive no more than another couple of miles before you have your car checked – and you should avoid driving at high speed and heavy acceleration.

Will Low Oil Cause the Engine Management Light to Come On?

Whilst low oil is a serious issue that you should fix right away, this is unlikely to cause the EML to come on as low oil has its own dashboard warning light.