‘Their problem’: Arizona man irked as Alamo Rent-a-Car rents him the wrong vehicle, but revenge could land him in legal hot water

An Arizona man, frustrated with Alamo Rent-a-Car over a vehicle mix-up, described his retaliatory plan in a TikTok video that could cause serious mechanical damage and legal liability, and according to some, stretched the limits of credibility.

In the video, @Factorywindowsaz explains, “So when I went to Alamo to get this car, I paid extra for a truck, and they didn’t have any trucks, so they wanted to give us a minivan.” After being upsold again, he added, “And then they made me pay extra to have an SUV.”

According to the man, the only clear instruction was to return the vehicle with a full tank of fuel. “So they said I had to fill it up, so I did,” he said.

He then alluded to what he believes is a clever workaround: “So every time I fill this up and dump it in the tank,” showing an empty liter bottle of water. “That’ll be their problem to deal with later.”

One comment noted he might be joking, and not actually putting water in the tank: “he’s filling it with water….at the gas station. doesnt sound sus at all.”

How water affects a gas engine

The commenter is right to be skeptical. We never actually see Factorywindows put the water in the tank. Furthermore, water and gasoline do not mix. Even small amounts of water contamination in a fuel tank can disrupt engine performance because gasoline engines cannot combust water.

Water in the fuel system can cause rough idling, hesitation during acceleration, and engine stalling. In more severe cases, water can accumulate and damage components such as fuel injectors, fuel lines, and fuel pumps due to corrosion and rust over time.

If enough water enters the combustion chamber, it can prevent the engine from firing or even lead to a hydrolocked engine, when water prevents pistons from moving and can damage internal parts. The result can be costly repairs or complete engine failure.

Rental agreements and liability

Beyond mechanical risks, deliberately introducing water or any contaminant into a rental car’s fuel tank could violate the rental agreement and risk financial and legal consequences. Rental contracts typically require renters to return the vehicle in the same condition they received it, subject to reasonable wear and tear.

Damage caused by negligence or intentional misuse—like contaminating the fuel—can make the renter liable for repair costs. If the renter purchased a damage waiver, that agreement may cover some costs, but waivers vary and typically don’t protect against intentional acts or misuse.

So, in the end, Factorywindows likely didn’t actually put water in his gas tank, but his point still stands, as he says in the voice-over: “Sometimes you shouldn’t rip off your customers.”