Many people complain they have water in their gas and most will blame it on a particular gas station. Most times, the gas station is not at fault, although there have been an occasion or two when they were.

Your vehicle's fuel tank is under the car and typically near the back. As such, it is out of the sun's heating rays.

Take something cold from your refrigerator and place it right outside your door on a humid day. Almost immediately you will notice condensation forming on the outside of the item. The longer it sits there, the more that forms until it will run down the outside and form a puddle at the base of the item.

Your gas tank gets water in it in a similar fashion. The tank warms up due to heat generated from the road when you drive. When you park the car, over time the tank cools. As it cools, moisture trapped inside condensates on the inner walls of the tank and just as the item removed from the refrigerator, the drops will eventually run down and into the gas tank.

Before ethanol, the gasoline would float on the top of the water and unless you had a major problem with water, the water would remain in the bottom of your tank (stirred when driving but settling out when parked).

Ethanol does not float on water but rather absorbs it. Instead of 100% gasoline (ethanol) going through your engine, you have a tiny percentage of water as well.

How is that a problem? Well normally, minute amounts of water will not cause any noticeable symptoms. Too much and your car will start to emit a white smoke cloud from the tail pipe.

Excessive amounts can cause engine problems, corrosion issues within the fuel system, and poor engine performance.

How to remove the water? Again, in the past it was a matter of draining the tank or adding an additive that claimed to dry up the water or otherwise whisk it out of the tank. Today, many of these products remain on the market, but are any of them made to remove water from ethanol; none that I have heard about.

Any possible additive has to accomplish two things, it has to separate the water from the ethanol and it has to somehow get the water out of the tank.

Some recommend concoctions of alcohols to dry your tank, but before you try one, consider any possible damages to your fuel system, seals, gaskets, engine combustion system, exhaust (including catalytic converter, if equipped) and emissions.

If you have a severe problem with water, the simplest solution is to drain the fluid from the gas tank and refill with fresh.

Is it possible to prevent water from getting into the gas? No, it will happen, however you can MINIMIZE the quantity of water by keeping your gas tank as close to full as possible. The less interior surface of the tank exposed to the air the less condensation there is to drip into the gas tank.

If you cannot afford to refill your tank from empty, fill your tank full and then retrain yourself to believe that is and is empty. This way, when you fill it from that mark you don't have the pump sticker shock a full tank would bring, and you keep more gas to fight the condensation.

Learn more about this author, B. L. Babb.
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