If your car smells like rotten eggs, then there could be a problem with anything from the catalytic converter to the battery.
Aside from the obvious unpleasant odour, ignoring this issue could actually be damaging to your health - especially if Hydrogen Sulphide is involved...
Find out what a rotten egg smell means for your car and what to do next by reading our useful blog.
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Should I Be Worried About a Rotten Egg Smell?
If your car smells like rotten eggs, you should be a little concerned.
A rotten egg smell can signal that something is wrong with your car that could pose a safety hazard or result in a costly repair.
The smell can usually be attributed to the gas Hydrogen Sulphide, which can cause sickness and nausea if you are exposed to it for a short time – and have long-term side-effects if you continue to be exposed to it.
You should stop driving your car if you think the smell is coming from your car’s air vents.
What Causes the Smell?
An eggy smell in your car can be caused by any of the following:
- A faulty catalytic converter
- A battery leak
- Old transmission fluid
- A faulty fuel pressure sensor
- A worn fuel filter
- Mould in the air vent system
Let’s take a look at some of the biggest issues mentioned in more detail...
Faulty Catalytic Converter
Your car’s catalytic converter is responsible for removing harmful pollutants from the exhaust gases and converting them into less harmful substances.
When the catalytic converter fails – often due to overheating, coolant leaks or structural damage – this can cause a sulfur smell to come from the exhaust.
You may also notice dark exhaust smoke and reduced acceleration and engine performance.
Leaking Car Battery
If your car battery leaks acid, this can result in a strong eggy smell – which will be most potent when you open the bonnet.
When a battery is working well, it is unlikely to leak.
Leakage will usually only occur if the battery has been physically damaged or over-charged, or if the battery is old or affected by extremely cold weather.
Over-charging, for example, can cause the battery to produce Hydrogen Sulfide, hence the egg smell.
You should not drive your car until the battery has been replaced.
Old Transmission Fluid
When your transmission fluid is old, leaks become more likely.
A transmission fluid leak can come into contact with the engine, thereby producing the rotten egg smell.
A mechanic can flush or replace the fluid for you if needed.
What to Do Next
If you smell rotten eggs, you should book an appointment at a professional garage ASAP and have the issue diagnosed and fixed.
No matter what is causing the smell, you should have your car looked at by a mechanic right away – even if the smell comes and goes.
Whilst you should be worried about a strange car smell, a mechanic will be able to check your vehicle and advise you as to the severity of the issue.
How to Get Rid of an Eggy Smell in Your Car
In most cases, the only way of stopping a rotten egg smell is by having the issue causing the smell fixed.
This could mean having a faulty component repaired or replaced altogether.
Keeping up with your car’s service and maintenance schedules can help to prevent the smell from developing in the first place and make early detection more likely, before any repairs are required.
