What does your check engine light do?
The engine management light, or 'check engine light', appears as a dashboard warning light usually found close to your car’s speedometer dial. If you see it, it means something either your engine or your exhaust. You'll often see the engine management light when you switch on your ignition, as all the dashboard lights quickly come on and then go off again as you start up your car.
However, if the engine management light stays lit or it comes on whilst driving, then it’s not simple to ascertain the issue without the help of a garage technician. Plus, there are a variety of reasons for the engine management light to appear.
Engine light diagnostics average costs
Specialist garages can use diagnostic scanners to ensure they can resolve the problem with your engine. The engine management light is connected to the engine control unit (ECU), which is the central computer of the car. Should the ECU detect an issue with the engine, it will turn the light on. Depending on the engine issue, the engine management light can be orange, red or flashing on and off.
The cost of a diagnostic to check out the engine management light can vary depending on your car due to differences in labour time and parts needed. Take a look below at the average quote on WhoCanFixMyCar for some of the top car makes.
|Car Make||Average Price|
Which engine management light service do you need?
If your engine management light has come on, it means there is a fault with your car and you should get it checked immediately. It could be one of a number of potential problems and can often be hard to diagnose without proper diagnostic equipment. It is advisable to have a mechanic take a look to provide a proper diagnosis.
The engine management light can be shown in different colours depending on how serious the problem is. It might even appear to be flashing. The vehicle handbook will help you understand the colours and reasons why the light is showing. Read on to find out typical issues you may encounter as a result of seeing the engine management light and what it could mean in terms of repair or servicing.
Engine management light repair
The average cost of an engine management light repair booked on WhoCanFixMyCar is £64.96.
When your engine management light comes on, it means that something is wrong with your cars engine and you should get it looked at by a professional as soon as possible.Can include
- Engine management light repair
The average cost of a car diagnostic booked on WhoCanFixMyCar is £48.
Car diagnostics testing involves plugging your vehicle into special software that can reveal issues with its engine, electrical system, transmission, braking, exhaust system, and more. A specialist will run tests on your vehicle to expose the cause of any problems you're having with your car.Can include
- Full diagnostic testing
- Recommended repairs
The average cost of a mobile mechanic booked on WhoCanFixMyCar is £62.54.
A mobile mechanic will visit you at your home or workplace and can carry out a wide range of different repairs. If the repair is more complex, the mechanic will collect your car, take it to a garage to be repaired, and drop it off when it's finished. The exact cost of a mobile mechanic will depend on the repair you need.Can include
- Home visit
- Tyre change
- Oil change
- Recommended repairs
What does the colour of the engine management light on the dashboard mean?
Amber engine management light:
The less serious problems are indicated by an orange or amber light. However, if the amber light persists, then you must take the car to the garage, but driving a few miles with caution should be okay.
Engine management light flashing:
A flashing orange light implies that there is a problem that could impinge on how the car drives or operates, such as an engine misfire. In this case, it’s not uncommon to feel the car shaking if you drive it, or the engine sounding different to usual. Take your car to a garage immediately if you see the engine management light flashing amber.
Red engine management light:
The most serious problems are indicated with a red engine management light and should you see this sign, you must stop at a safe place and call a breakdown service or a local garage that is open immediately. Do not attempt to continue driving the car if you see this.
What can cause the engine management light to come on?
As the engine management light doesn’t inform us of one particular problem, it’s hard to say what definitely causes the engine management light to come on without diagnosing the issue. One thing you know for certain though, is that the engine management light will come up to signal that something is wrong with your car. There are some common reasons that are diagnosed as a result of the engine management light and we will explore them below.
Blocked diesel particulate filter
A blocked diesel particulate can be indicated by an amber engine management light. A diesel particulate filter (DPF) is installed on diesel-powered cars to catch soot from the exhaust and cut down your emissions. It is likely for it to come to be obstructed and then cause your engine management light to turn on, but this isn’t classed as a major problem. You can generally fix this problem by driving somewhere with a faster speed limit. A thirty-fifty minute trip at a sustained high speed on the motorway often clears the filter. However, if this doesn’t do the trick, then take the car to your local garage for inspection.
Loose petrol cap
A loose petrol cap is one of the most common reasons for the engine management light to show on the dashboard. Check the cap to see if it is cracked or damaged. If it is, then you will need a cap replacement.
If you’re driving a petrol car, problems with your spark plugs, which are there to transfer electricity from your ignition to the engine, when turned on, can set off the engine warning light. Your local garage will be able to check if one or more spark plugs need to be replaced and then turn off the engine light.
The catalytic converter is damaged
An engine light can show if your catalytic converter is damaged or it has stopped working. This part makes up a section of the exhaust system and is vital for converting carbon monoxide and other dangerous compounds. If there is an issue with your catalytic converter then you’ll notice an increase in the fuel consumption of your car and you will not be able to accelerate properly.
This part is mostly susceptible to damage if other parts fail, such as the oxygen sensors and spark plugs. If the part stops working, deadly carbon monoxide will be emitted from your car and this could be seriously dangerous.
If the part fails then it will need to be replaced.
The mass airflow sensor
The light in your car will switch on if the mass airflow sensor becomes faulty or breaks, however, it is possible to drive despite the part failing. The engine light will come on if the air filter on the airflow sensor isn’t properly installed or needs replacing. You should be replacing the filter at least once a year to ensure the sensors work properly all the time.
The MAS (Mass Airflow Sensor) is an important part of the car engine. But it can be faulty and not have a hugely detrimental effect on the car. However, that doesn’t mean that you should ignore the issue as this could lead to a bigger problem.
Replacing the air flow filter is a relatively simple job so it should not be an expensive or time-consuming job for a mechanic.
Failing spark plugs
If the engine light comes on and you have checked all the above, the final thing you should check is your spark plugs. Spark plugs are in place to initiate the combustion in the car when it starts. If they are failing, then you should notice some jolting when you accelerate.
Fortunately, spark plugs are relatively simple to replace and are cheap to buy brand new. A mechanic will take no time at all when replacing the failed parts and this is a job that you may be able to do yourself, though we wouldn’t recommend it unless you have a good understanding of a car’s engine.
Other engine warning light causes
The engine light in your car will come on for a huge variety of reasons and the ones we have listed above are simply some of the most common. Even if you know what the problem is, it’s vital that you take your car to a garage as soon as the engine light comes on, as ignoring it will inevitably result in you suffering from a more serious issue and spending more money on repair.
If you’re unsure of why your engine warning light has come on, you can have a mechanic run your car through a couple tests to determine and then fix the issue at hand.
Why is diagnosing and fixing the engine management light necessary?
Sometimes, you’ll find you are able to drive the car a few miles, but to ensure no further damage is done to the car, which can lead to extortionate garage bills, then take it to a garage near you. If the engine light comes on while you're driving, don't panic. Instead, pay attention to see if the car is performing differently to usual, and book the car in with a reputable engine failure garage as soon as possible. The cause could differ from car to car, from a faulty oxygen sensor to a loose fuel cap. It could also mean your catalytic converter has failed and quit working.
Find garages to check your engine management light
Looking for engine management light specialists near you? You will find the best engine management light and engine failure mechanics and garages in your area below.
You can take your car to your local engine failure garage, where they will check the engine management light and diagnose with an OBD2 diagnostic scanner. This will give them a code to determine the problem.
We work with a network of over 15,000 mechanics and garages across the UK so we can find competitive engine diagnostic and repair prices for you. You can then compare the quotes and read reviews from previous customers to find the best engine repair deals before booking the local garage online.
How much does it cost to fix your engine light?
The cost of repairing your check engine light will depend on the make of your car, and the garage you visit, however an average figure for a engine management light is around £64.96.
What causes the engine management light to come on?
The engine management light monitors the health of a number of different components, including: fuel pump, spark plugs, oxygen sensor, catalytic converter or airflow sensor. In other words, the fundamental components controlling air and fuel flow through the engine. It comes on when one or more of these is faulty.
How do I turn the check engine light off?
The light most likely won’t go off by itself. You need to take your car to a garage to get the problem diagnosed. When the problem with your car has been found and repaired and the vehicle is operating smoothly again, the technician at work on your car will retune the car's ECU so that the engine management light goes off. Sometimes the system will need a second reset.
Does an engine management light affect my MOT?
An engine management light isn't an MOT failure in itself, and will likely be marked as an 'advisory note'. However the underlying issue could still cause an MOT fail (for example, faulty airflow meters causing poor running and high emissions). We always recommend resolving an issue with your engine management light prior to your MOT, to avoid failure.
Is diagnosing and repairing the engine management light problem part of warranty?
If your car is covered by warranty, then the good news is that when your check engine light comes on, your warranty will very likely cover what’s wrong. It’s important to check the warranty agreement to ascertain whether this is the case for your car.
What components are linked to the engine management light?
The engine management light indicates an issue with one or more of the following: fuel pump, spark plugs, oxygen sensor, catalytic converter or airflow sensor. Your car may still be drivable but will be performing below optimum power and efficiency.