Diagnose Car Problems & Find The Right Fix

Ellie Dyer-Brown, 1 month ago

5 min read

  • Advice
  • tips
A mechanic discussing a car diagnostic test with a man in a blue shirt next to a white car with the bonnet open.

WhoCanFixMyCar discusses how to diagnose and fix common car problems.

Cars are complicated, expensive machines - bottomless money pits, as people often joke. After you’ve paid for your insurance, road tax, fuel, MOT and annual service, the last thing you need is another trip to the garage. Should you turn the music up louder and ignore the problem? It can certainly be tempting.

Judging by the fact you’re reading this, you know the head-in-the-sand approach is not a good idea. Instead, it’s best to tackle whatever issue you're facing directly, which is why we’re going to help you identify what’s wrong with your car and find a solution in the easiest, most pain-free way possible.

Select the option below that applies to your situation.

I’ve noticed an unusual smell in my car

Unusual smells can be unpleasant and embarrassing. Most of the time, it’s easy to diagnose the problem by identifying what your car smells like - whether it’s fish, mould, petrol or something else. After that, it’s worth noting where the smell is coming from, as doing so may narrow down the cause. 

iStock-car smell

Choose the option below that best describes what you can smell.

Why does my car smell of fish?

A fishy smell may be caused by mould, leaking antifreeze or a dead animal. There are a few home remedies you can try to eliminate the smell of mould, but if you’ve got an antifreeze leak, your car will need professional attention.

Find out more about the possible causes of a fishy smell and how to fix them in this guide.

Why can I smell petrol in my car?

The first thing to do when troubleshooting the smell of petrol is to work out whether it’s coming from inside or outside your car. On the inside, it could be caused by loose spark plugs; on the outside, it may be caused by a loose petrol cap, faulty injectors or a fuel leak. Either way, you’ll probably have to take a trip to the garage. 

This guide covers all the possible causes of a petrol smell in detail, with advice on how to fix them.

Why does my car smell of burning rubber?

Often, drivers smell burning rubber when changing gear, which is a sign the clutch is overheating. If you notice the smell while driving, a loose rubber hose could be to blame. 

Learn more about the potential causes of a burning rubber smell and how to repair them here.

Why does my car smell like rotten eggs?

The most common explanation for a rotten egg smell is a faulty catalytic converter. Other possible causes include a battery leak, defective fuel pressure sensor, old transmission fluid and a worn-out fuel filter.

Click here to discover why your car smells like rotten eggs and what you can do about it.

I’ve noticed an unusual noise in my car

Most drivers are attuned to the noises their cars make and immediately notice when something is different. As tempting as it can be to ignore the sound by turning up the radio, it’s better to confront the problem sooner rather than later since it could get worse.

We have a range of guides to help you diagnose the cause of unusual noises and find a solution.

Unusual noises

Finding the right words to describe the sound you’re hearing can be tricky, but the closer you get, the easier it will be to work out the cause. Below, we’ve compiled a series of guides exploring the most common sounds drivers report.

My car is making a…

My car sounds louder

If your car isn’t making an unusual noise but sounds louder than usual, it’s still worth investigating whether there’s a problem. The first thing to do is determine whether it is more audible at the back or front end. Possible causes include a damaged muffler or faulty exhaust.

Close-up of car exhaust

My car is misfiring

Misfiring is not only unpleasant for you and anybody in the vicinity of your car when it happens, but it could also be a sign of a problem that requires attention from a trained mechanic. 

Our guide to engine misfiring covers everything you need to know, including what a misfire is, how it feels and what could be causing it.

My car alarm keeps going off

Car alarm repair image

When your car alarm goes off for no apparent reason, it could indicate various problems, including a low car battery, wiring problems or a faulty door lock sensor. Most of the time, you’ll need to enlist the help of a car alarm repair specialist.

Read this guide to discover all the things that could make your alarm go off and how to fix them.

I’ve noticed an unusual feeling in my car

From the tremor of the clutch when you haven’t quite found the biting point to the rumble of the engine, most of us are well acquainted with the feel of our cars. That’s why, as soon as there’s a small change, we notice.

The following guides will help you work out what could be wrong with your car based on the unusual feeling you’re experiencing while driving.

Wrong temperature

Problems with your aircon or car blower are less than ideal - especially during the peak summer and winter months when you rely on them to regulate the temperature inside your car. 

Warning lights

ABS warning light

The last thing you want to see when you start your car is a bright engine warning light glowing on the dashboard or your headlights flickering ominously. We’ve created a series of guides to help you navigate both situations.

My car is giving out smoke

Seeing unusual smoke from your car can be alarming, but there’s no need to panic. It could be something as simple as low coolant. However, there are several more serious causes, so smoke should never be ignored.

There’s something wrong with my tyres

Man's hand pointing at car tyre tread.

Checking your tyres regularly for signs of wear is an essential part of car maintenance that should be taken seriously. Take a look at the guides below for information about diagnosing tyre problems, such as a lack of pressure or low tread.

Book a repair

Once you’ve diagnosed the cause of your car troubles, WhoCanFixMyCar is here to help you get them fixed for an affordable price.