Before getting into the car, you should quickly look at the ground beneath the vehicle. A stain or small puddle may be water, but it can also reveal an oil leak, coolant, fuel or other fluid leak. RAC, a British roadside assistance company, recommends observing the origin and characteristics of the fluid to understand what may be happening. It is important to confirm that the stain came from that particular car, as in a shared car park or on the street it may have been left by another vehicle.
Not all water under the car is a sign of a fault. If it is transparent, odorless and similar to water, especially after using the air conditioning, it may simply be condensation produced by the system. The AA, the British automobile association, explains that this is one of the most common causes of water under a car and usually does not represent a fault. However, if the origin is unclear, the amount increases or other signs of abnormality appear, you should seek a professional assessment.
The color of the fluid can provide important clues. According to the AA, engine oil usually has brown or black tones, while coolant can be different colors, such as green, yellow or pink. RAC clarifies that there are coolants of various colors, including transparent ones, so the absence of color is not enough to guarantee it is simply water. A technique suggested by RAC is to place white cardboard under the car to collect a few drops and better observe their appearance.
There are situations where you should not continue driving. An oil leak, even a small one, should be assessed and if the oil pressure light comes on, you should stop immediately. A strong smell of petrol or diesel deserves particular care due to the fire risk. The AA also advises against driving if there is a suspected brake fluid leak, as it can compromise braking. A leak may become visible before it causes conditions that trigger a dashboard warning light, so you should not assume everything is fine just because no light has appeared.
