There are few things worse than failing an MOT. Arguably, one of those is seeing your engine light come on. But does one lead to the other?
Does The Engine Light Being On Fail Your MOT?
Yes. If you take your car to have its MOT test and the engine light is on, it will be an instant fail. This light indicates that something could be wrong with the vehicle that means it’s unsafe, or it might mean that the car is producing too many nasty emissions.
Don’t forget, your car can fail its MOT because of bad emissions! Here’s what you should do if that happens.
Why Does The Engine Light Come On?
The engine management light, as it’s formally known, is one of the many lights that might pop up on your dashboard from time to time. This one indicates a problem with your engine. Unfortunately, the engine light can often mean that something serious is wrong with your car.
However, that’s not always the case. Simple problems might also cause the engine light to illuminate, so don’t panic!
The engine light often comes on because of a problem with your:
- Oxygen sensor – This measures the air in your fuel to ensure it’s kept at an appropriate level. If there’s too much or too little air in the fuel lines, the engine management light (EML) will come on. However, the light might also come on if the sensor itself breaks.
- Catalytic converter – One of the most expensive parts of any car, this helps reduce the emissions that come from your vehicle to a less harmful standard. If it breaks, your engine could be in danger of damage.
- Diesel Particulate Filter (DPF) – This reduces the amount of soot in your exhaust, but can become blocked. If this happens, your emissions will be much more harmful and your EML may turn on. Don’t panic, though; there are ways to unblock it!
- Mass airflow sensor – This part tells the car how fuel needs to be sent to the combustion chamber to keep the car running properly, but if it stops working as it’s supposed to, it could result in engine damage and the EML illuminating.
- Spark plugs & coil pack – These parts work in tandem to kick off the combustion process and keep the car moving smoothly as it drives. However, if they start to malfunction, the car might become juddery and the EML can come on.
- Oil – If your engine oil is old, or even if the level of oil in your car is drastically low, the EML might come on.
Should I Keep Driving My Car With The Engine Light On?
You can, but that doesn’t mean you should. When your engine light comes on, it’s a good idea to get the vehicle checked out as soon as possible to avoid any problems getting worse. However, if your engine light is yellow, you’re not likely to be in immediate danger of a breakdown.
On the other hand, if your engine light is red, you should stop the car and not continue driving. This could indicate a serious malfunction that’s occurred – or is about to. Carrying on your journey could prove dangerous, or do long-term damage to your car!
What Do The Colours Of The Engine Light Mean?
You might have seen your engine management light pop up once or twice and started to worry, but if you’ve only had it light up amber in colour, the situation could be worse.
Yellow
Yellow (or amber) means that something is wrong, but that the problem is not going to cause you any immediate concerns or danger. You can continue to drive around with your yellow Engine Management Light on, but should probably try and get to the root of the issue soon.
Blinking
A blinking or flashing yellow light means the problem is more serious. However, it’s still not likely to be a life or dead situation. You should, however, think about taking the car to a professional to have the matter investigated as soon as you can.
Red
A red light is much more severe. If your EML is on, and it’s red, you should pull over as soon as it’s safe to do so and call your recovery service to come and collect your car. Continuing to drive it could do fatal damage to your vehicle, and may even result in a dangerous accident if your car fails at the wrong time.
How Much Does It Cost To Fix An Engine Problem?
Generally speaking, you’re looking at several hundred pounds. Of the above, an oil change will be the cheapest – a bottle can be as cheap as £10 in most places. Spark plugs and coil packs are also an easy fix that’s relatively cheap.
Moving up, you’re probably looking at £100 to £500 for problems involving sensors, and up to £1,000 if you’re in need of a replacement catalytic converter. However, the big money problem lies in the DPF… Diesel drivers could up paying thousands of pounds for a replacement diesel particulate filter. Luckily, they often have their own warning light on the dashboard which should light up separately!
What If I Can’t Afford The Repairs?
Engine problems can be so expensive that they’re simply out of your budget or not worth it, particular on older cars. This is just something that every driver needs to be aware of, especially when the maintenance of their car is entirely their own responsibility.
Can’t afford to get your car fixed? Don’t want to spend thousands on a new engine for your old banger? Have a look at how much money you could make by selling your vehicle with Scrap Car Comparison. Even if the engine is already dead, we’ll quote you a top price!
How Can I Prevent My Engine Light From Coming On?
This can be summed up in one word: maintenance.
Your car can’t look after itself. A bit like a pet, it can give you endless joy and loyalty, but only if you look after it! Regular servicing, checking of oil & fluid levels, using fuel additives, identifying aging parts before they break… all of this can keep your car on the road for longer.
Engine Light FAQs
Will my engine light go off on its own?
Usually, no. If the engine light has come on, it’s because there’s a problem with the car. However, turning something off and on again can work wonders for any machine. It is possible for your engine light to simply be on one day and off the next – but don’t assume whatever issue caused it has fixed itself!
Can I turn the engine light off myself?
You can, but probably shouldn’t. On some vehicles, turning off the electronics (with a partial turn of the key in the ignition) and turning it on again several times can clear the engine light.
A more sensible way of doing it is to invest in an on-board diagnostics kit (OBD) which you plug into your car. Once connected, this device will read your car’s systems and attempt to tell you what is wrong with it! Not only is this a good way of actually figuring out what the problem is, you can also clear the engine light.
Why is my engine light on but my car feels normal?
Not every problem with your vehicle will have an immediate or obvious impact on the way it drives. The same goes for issues that cause your EML to illuminate. The thing is, if these problems are left alone, they will almost certainly get to a point where they do impact the car’s performance and might even end up needing a massive repair job.
