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Reading the signs to maintain engine health
A new noise, leak or smell could be telling you that something is wrong with your car. These signs could lead to expensive problems, so if you see or smell something, don’t ignore it.
Things to look out for
Smoke from your exhaust
If there is smoke coming out of your exhaust, make a note of whether it is black, blue or white. If the smoke only occurs when the car is moving, ask a friend to drive behind you and describe the smoke. This will prevent you being distracted while driving.
Black smoke is caused by raw fuel being burnt in the exhaust. This can be the result of a badly adjusted carburettor (or fuel injectors, if fitted) or a blocked air filter. If you only get black smoke first thing in the morning, it is likely that the choke or the fuel-enrichment section of your fuel injection system need adjustment. Your local franchise dealer will confirm the cause and fix the problem for you.
Blue smoke indicates that oil is being burnt. Unfortunately, continuous blue smoke is likely to be expensive as it indicates the piston rings or cylinder walls are damaged. If all you get is a quick puff of blue smoke in the morning, then the problem is probably bad valve guides or valve-guide seals. This is less serious but still needs prompt attention from your franchise dealer.
White smoke could be due to coolant or antifreeze that is either leaking, or being forced into the combustion chambers and being burnt. A leaking head gasket, broken head or damaged cylinder wall are the most likely causes of the problem, but ask your franchise dealer for their opinion before embarking on a repair.
Being aware when you approach your car and keeping an eye on your mirrors while driving can often give you the first indication that something is wrong with your car. If you are not confident about identifying or fixing the problem yourself, discuss your observations with your local franchise dealer. You should give them as much information as you can to help identify the cause quickly.
If you spot a leak make a note of whether the car was parked on a slope, where under the car you noticed the leak and the colour of the fluid. For example, green fluid under the front of the car is likely to be engine coolant. Have a look at the temperature gauge to check the car is not overheating and ask your local franchise dealer to find and mend the leak.
Unusual smells can come from the car in front or your environment, but if the smell is consistent it may well come from your car. When describing the smell to your franchise dealer try to remember if it was:
- a sweet smell (likely to be caused by burning engine coolant)
- acrid, like burnt plastic (likely to be caused by electrical faults)
- like burning rubber (likely to be caused by overheating brakes or clutch).
Whatever the cause, discuss the problem with your franchise dealer.
A car can make numerous sounds, from knocks and rattles to grinds, squeaks and hisses.
Try to find a term that describes the noise you hear and whether the noise is intermittent or continuous. If it is intermittent, make a note of whether it occurred when the engine was hot or cold, whether you were accelerating or driving at a constant speed and if there were any unusual instrument readings at the time. Your franchise dealer will appreciate the additional information and it will help reduce the time needed to solve the problem.