Have you spotted water pooling under your car? If you're a new driver or you've seldom seen fluid leaking from under your vehicle, the sight can be worrying. In most cases, however, it does not indicate a serious issue.

Coolant leak

If the fluid turns out to be coolant rather than water, you could have a serious problem. Coolant is usually green, blue or yellow and has a sweetish smell. Normal water will of course be clear and odorless. If your car is parked in a dark location or the ground is dark, it may be difficult to determine if the fluid is coolant or water. Try dabbing a piece of paper or an old cloth in the puddle so you can have a closer look.

 

Unless someone mistakenly put straight water into the coolant chamber, the presence of clear water does not suggest a coolant leak.

 

Causes of a coolant leak

Coolant may leak from a car for a number of reasons. The most common are: radiator corrosion; a damaged coolant hose; or a water pump with a leaky gasket. Unless you have mechanical expertise, if you spot a coolant leak you should take your car to your garage. They will be able to pinpoint the issue and replace the damaged component.

 

Any coolant leak suggests your car has a serious problem - since your engine depends on coolant for its cooling system to work. You should be able to drive your car a short distance (to the garage, for instance) if you first top up the coolant level.

 
Condensation from the air conditioning system

In the vast majority of cases, water leaking from under a vehicle is usually condensation from the air conditioning system, or from the exhaust.

 

If you see water around the rear of the engine compartment, it's likely to be AC condensation.

This is normal and is nothing to worry about. 

 

Water around the exhaust suggests exhaust condensation. In most cases, exhaust condensation is also nothing to worry about, unless there are very large clouds of white condensation coming from the exhaust. Such a large volume of condensation suggests coolant has found its way into the combustion chambers and is burning alongside the air-fuel mixture. This in turn may mean the head gasket has blown.

 

Just about to go on a long drive?

If you spot water under your car just before you set off on a long drive, you may wonder whether you should postpone your trip. If you think there is a coolant leak, it is advisable to visit your nearest garage. But if there is water under the rear of the engine compartment, it is most likely just condensation from the AC unit - and you can continue your journey as planned. In the case of a leak around the exhaust, as long as your coolant levels are good, it doesn't suggest a problem.