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Two contents of the exhaust are of primary concern.
The first is CO (Carbon-Monoxide), which is a colourless, odourless gas that is highly toxic, even in low concentrations.
The second is not a gas as such but a class of gasses called "Hydro-carbons," which are basically unburned fuel. These are a major contributor to Photo-chemical Smog, and are also toxic.
Both the above are generally produced when the engine fails to fully burn all the fuel, and are generally a sign that the engine is not running correctly.
The third gas is Oxygen, as in theory there should be no oxygen in the exhaust, as it will have all be used up burning the fuel. This is not so important as oxygen in the exhaust is not in it self harmful, just indicative of a fault.
The exact reading (expressed as a percentage for hydrocarbons and oxygen and as PPM <Parts-Per-Million> for hydrocarbons) varies depending on the age the car was first used.
For very old cars (Pre war) there is no test as such, all that is required is that the vehicle is not "Visibly Excessively smoking" as when the car was made the technology at the time was not capable of making the car meet any tougher test than this, nor was the danger pollutants as well understood as it is today, and also there were far fewer cars- the number of cars on he road then probably produced less pollution (in total, all added up) than todays cleaner cars- so it did not matter as much that they be clean.
The above applies to petrol vehicles, diesel vehicles are tested in a way not directly involving gasses.
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What can you do if you lose your MOT?
Appeals against MOT inspectionsIf a motorist who has recently had a vehicle MOT tested disagrees with the outcome of the inspection, they are entitled to an appeal against the decision. Without an MOT they cannot drive their cars.
What things are tested in the UK car MOT?
seat belts suspention
Do police cars have mot's?
Yeah, so police cars just have mot's. It's always been like that and will in all probability always remain be that way, too
Do cars pass mot in Northern Ireland with a service light on?
no
What does fsh mot mean for UK cars?
Full service History
How can you find out if a car has an MOT?
You can check your cars MOT details by going to http://www.motinfo.gov.uk/ and entering your Logbook or V5 registration document number.
What does most cars fail the mot on?
Brakes and passengers puking upon the seats, not nice.
Do American cars need an MOT?
yes they do. but what is categorised as safe and legal is different in different states.
My friend has no tax or mot or insurance as his car has been of the road for some time i am thinking of buyin it can i drive it home with insurance only?
No, but you can book an MOT test for it and you are then legally entitled to drive it to the MOT testing station, provided that you are insured. Once it has been tested you can then legally drive it home from the MOT testing station, providing it has not been deemed to be "unsafe to drive."
Are front fog lights tested as part of UK car MOT?
yes. they are part of car so need to be included in the MOT. If your driving in fog you need to use fog lights, so they need to be in working order.
Why choose InterCar and van for MOT Test in Northampton?
InterCar and van is a reliable and experienced MOT testing centre in Northampton. They offer a comprehensive range of MOT tests for all makes and models of cars and vans. Their experienced and qualified technicians are able to carry out all types of MOT tests, including Class 4, and Class 5.
How do people check the pollution of cars?
They have the emissions tested.
