What to put in a car’s gas tank to ruin the engine? What kind of things will ruin a car engine if we put it into the gas tank? What will ruin a car engine? There are many things can ruin a car engine if the material in the gas tank is not gas or diesel depending on the engine. Some will destroy the engine completely, some will make the engine burn, and some will simply stop the fuel flow and make the car engine can’t start (see car engine won’t start). It depends on how you want to ruin the engine.

Here is the list of things that you can put into a car’s gas tank to ruin the engine and the result of what will happen to the engine. This list is for everyone to avoid putting things that can ruin the car engine into the gas tank. DO NOT DO THIS AS A PRANK TO ANY CARS. See some of the greatest car pranks that are harmless to cars if you just want to play a car prank with friends.

1. Bleach – Bleach in a gas tank will cause damage to the car engine and it can cause rust in the gas tank. Bleach can ruin an engine very fast.

2. Cigarette Butt – Yes it will!

3. Molasses, Honey, Pancake Syrup, Waffle Syrup, Maple Syrup or sticky liquid – All these things are sticky liquid, it will stick to the pickup screen or block the fuel pipe and the fuel flow will be stopped. It won’t bring big harm to the car engine if it did not flow to the injection or carburetor.

4. Sugar – Some research said sugar doesn’t dissolve in gasoline and it sinks to the bottom of gas tank. It will stop by fuel filter even it travel through the fuel pipe. However, fuel filter can’t stop 100% of the sugar and if it go into the engine, the answer is YES, it will ruin it.

5. Diesel in a car’s gas tank that required unleaded fuel – This accident happen occasionally because gas station (petrol station) always have diesel and unleaded fuel pump. If Diesel runs into the engine’s cylinder, the spark plugs would still fire but nothing will happen and the engine will never start. This is because diesel fuel doesn’t evaporate as well as unleaded fuel. If you have accidentally put diesel fuel into car that requires unleaded fuel only, drain all the diesel fuel and refill it with gasoline. Crank the engine for few minutes until the diesel is fully out from the fuel lines and the injectors. The car will start and run fine, it will not bring any damage.

6. Gasoline in a diesel engine – It is almost similar with putting diesel in an engine that required unleaded fuel. It will not bring damage to the engine but immediate action must be taken. The fuel must the drain and replaced with diesel fuel.

7. Urine or Pee – It may not ruin the engine but it will damage the fuel filter. Fuel filter will stop anything that is not fuel and it could be spoilt by urine or pee.

What to do if these things run into the gas tank?

For Bleach, if it has ran into the engine, the car would have tow to a mechanic for full overhaul and an engine replacement if it is very serious. Do not start the car if cigarette butts, molasses, honey, pancake syrup, sugar, or sticky liquid, or anything similar run into the gas tank. Tow the car to the nearest workshop and get a mechanic to remove it all from the gas tank. Be prepared to replace a new fuel tank in the worst case.

One best way to prevent anything like this to be happen is to buy a locking gas cap and prevent it from happen as well as prevent thief to steal the gas from the car. So now you have understood what to put in a car’s gas tank to ruin the engine, PLEASE DON’T DO IT OR EVEN TRY IT!