23 Weird Things You Should Never Do to Your Car

Let’s get straight to the point: you love your car, and you want to keep it running smoothly for as long as possible. But sometimes, what you don’t know can hurt your ride. Here are 23 things that, frankly, you should never do to your car. 

Ignoring Flickering Lights

Flickering lights on your car are a sign that something is messed up with your electrical system. It could indicate that your bulbs are about to go out or that there’s a power leak or a failing battery. If you notice flickering lights, it’s important to address the issue ASAP. If the flickering occurs when starting the engine, it may be a sign of battery issues. If that’s the case, have your battery checked by a professional to make sure it’s working right and doesn’t leave you stranded. 

Riding Your Brakes Downhill

Constantly braking when going downhill can cause your brake pads and rotors to overheat, which can lead to added wear and the risk of warping. A better approach is to use engine braking by shifting into a lower gear. This allows the natural decompression of the drivetrain to help control your speed. 

Disregarding Rust

Ignoring rust on your car is a major no-no. Rust is a silent killer, and it’s usually worse than it looks. Small rust spots can grow fast and compromise the integrity of your car’s body. Make sure to fix rust issues as soon as possible by stripping, filling, and repainting any affected areas. Even minor surface rust needs attention to stop any further damage. 

Using the Wrong Coolant

The coolant in your car’s cooling system is not a one-size-fits-all solution. Different engines need specific types of coolant to be compatible with the metals, plastics, and rubber materials in the system. Using the wrong coolant or mixing different types can lead to serious issues like premature failure of the water pump, radiator, heater pipes, and heater core. Incompatible corrosion inhibitors in the coolant can reduce the effectiveness of the additive package in your car’s existing coolant, which can lead to damage to seals and gaskets over time. To avoid these problems, always use the coolant listed in your owner’s manual. If you can’t find the right coolant at an auto parts store, it’s worth getting it from a dealership. 

Pouring Hot Water on Icy Windshields

Never, I repeat, never pour hot water on an iced-over windshield. The sudden temperature change from the hot water can cause your windshield to crack and even shatter. Pouring cold water on an icy windshield isn’t a good idea either because it can cause the water to freeze, making the situation worse. Instead, use a good ice scraper and de-icing methods, like a de-icing spray or your car’s defroster, to safely remove ice from your windshield.

Mixing Brake and Power Steering Fluids

It’s surprisingly easy to confuse brake fluid and power steering fluid bottles, but mixing them up can be a really expensive mistake. Power steering fluid can swell the seals in the brake system, which can lead to total brake failure. Brake fluid in the power steering system causes pump and steering gear failure due to its lack of lubricating properties. Do yourself a favor and always double-check the fluid type before adding it to your vehicle.

Disconnecting Battery for Alternator Test

Testing your alternator by disconnecting the battery cable was a common practice in the past, but it’s a dangerous gamble on modern cars. Today’s vehicles are made with sensitive computers and electronics that can be damaged by the voltage spike caused when you disconnect the battery. This method might have worked on older, non-computerized cars, but on any vehicle built after the early 1970s, it’s a surefire way to fry your car’s electronics, leading to expensive repairs. 

Resting Your Hand On the Gear Shifter

If you drive a manual transmission car, it can feel natural to rest one hand on the gear shifter. I know it doesn’t seem like a big deal, but it can actually put unnecessary strain on the transmission’s bushings and synchronizers, which can lead to premature wear. It’s better to keep both hands on the steering wheel for the best control and to prevent transmission damage. 

Ignoring Oil Light Warnings

The “low oil pressure” warning light is your car’s way of telling you something is wrong. Whether it’s due to low oil levels, a leak, a clogged oil passage, or a failing oil pump, you need to act immediately. If this light comes on while you’re driving, make sure to pull over safely and shut off the engine. Check the oil level using the dipstick. If you’re low on oil, add more before restarting the engine. If the dipstick shows you have enough oil, the problem is more serious, and you should take your vehicle to a mechanic. In this case, it’s actually safer to call a tow truck than risk further damage by driving.

Revving a Cold Engine

Revving your engine immediately after starting, especially when it’s cold, can actually hurt your car. Let your car idle for a minute or two after starting to give the oil time to circulate and the engine to warm up. Cold revving can cause abrupt temperature changes that stress the engine’s components. 

Driving on Low Fuel

Consistently driving your car with less than a quarter tank of gas is a bad habit that can cause premature fuel pump failure. The fuel pump is housed inside the tank and relies on the surrounding gas to keep it cool and at a safe operating temperature. Driving with low fuel levels can’t provide sufficient cooling, which could cause the pump to overheat. Low fuel levels also increase the risk of the pump sucking in debris from the bottom of the tank, which can wear out the pump and cause low fuel pressure issues. 

Using the Wrong Engine Oil

Today’s cars have fancy parts like variable valve timing and turbochargers that need specific oil types. Using the wrong oil can mess up these parts and even damage your engine. If you don’t use what the car maker recommends, you could end up with big repair costs. So, always use the oil type and thickness that your car’s manual tells you to.

Washing Your Car with Dish Soap

Don’t wash your car with dish soap. While it may seem like a clever idea, it’s actually hard on your car’s paint. Dish soap strips off the wax and oils that keep your car’s paint protected. Over time, this can make the paint fade and get damaged. Stick with car wash soap instead. 

Neglecting the Oil Dipstick

If you really want your car to last as long as possible, then you need to be intentional about checking the oil. Engines burn a bit of oil over time, and not topping it up can strain what’s left, reducing its protective power. Letting oil levels drop too much could lead to engine damage and expensive fixes.

Leaving Drinks in Freezing Temperatures

Leaving drinks in your car during freezing temperatures is a recipe for a messy disaster. When liquids freeze, they expand, which can cause containers to burst and spill all over the inside of your car. You can avoid all of this by taking your drinks in with you anytime you leave your vehicle.

Smoking at the Gas Pump

Lighting up a cigarette or using a lighter at a gas pump? Bad idea. Gasoline fumes are like a ticking time bomb – just a tiny spark from your cigarette or lighter, and you could set the whole place on fire. Seriously, keep the lighters and cigarettes in your pocket when you’re filling up.

Driving Barefoot

Driving without shoes might seem comfortable, especially when you know you’re going to be driving for a long time, but it’s not the safest choice. When you drive barefoot or with only socks on, you may not be able to apply the necessary force to the pedals, especially when you need to break unexpectedly. This can reduce your reaction time and control over the vehicle.

Overinflating Tires for Better Mileage

There’s a “hack” out there that says overinflating your tires will give you better mileage. This is a misguided strategy. Overinflation can lead to lots of problems: a rougher ride, uneven tire wear, longer stopping distances, and more strain on suspension components. The optimal tire pressure for your car takes into account vehicle weight and handling dynamics. While inflating to the maximum pressure might be okay when carrying heavy loads, you should revert to the recommended pressure afterward. Overinflated tires reduce rolling resistance, which might increase mileage a little, but they also cause poor traction, especially on wet ground, and encourages wear on both the tires and the entire suspension system.

Ignoring the Parking Brake

Many drivers (myself included) forget about the importance of using the parking brake, especially on level surfaces. However, relying solely on your car’s transmission to hold your car in place puts strain on your parking pawl. Over time, this strain can lead to breakage, which can cost you a pretty penny. 

Rapid Shifting from Reverse to Drive

Quickly shifting from reverse to drive without coming to a complete stop is a habit that can do some damage to your car’s drivetrain. This abrupt change in direction puts stress on your engine, transmission, and axles. While it might seem like a time-saver, in the long run, it can lead to some pricey repairs. 

Unnecessary Hard Acceleration

Listen, I get it. The temptation to floor the gas pedal for a quick burst of speed can be hard to resist, but it’s not good for your car. Hard acceleration puts a heavy load on your car’s drivetrain components, which can lead to increased wear. To maintain your car’s condition and efficiency, drive smoothly and do your best to resist the urge to push your car to its limits.

Carrying Excess Weight

The weight of your car has a direct impact on its performance, fuel efficiency, and wear on drivetrain, suspension, and brakes. So, keeping your car as light as possible can make a big difference over time. While you don’t need to go to extremes, it’s a good idea to clean out any unnecessary items from your car. Even a few pounds of extra weight can affect your car’s fuel consumption and handling. 

Choosing “Universal” Fluids

The temptation of “universal” fluids for power steering and transmission systems is strong, but it’s a risky choice. Despite what they claim, these fluids often fail to meet the specific requirements of different car makes and models. The viscosity and additive requirements for transmission and power steering fluids vary between European, Japanese, and domestic vehicles and even between different models and years within the same brand. Using a non-approved fluid can lead to damage. Always refer to your owner’s manual for the recommended fluid type and, if necessary, purchase it from a dealership or a store that stocks the exact match.