The Dos and Don’ts of Pressure Washing Your Car: A Beginner’s Guide

Last Updated on December 13, 2023 by John Robinson

Washing your car with a pressure washer can be a great way to save money, avoid long lines, and always get satisfactory results. But, naturally, a pressure washer is a powerful tool used to clean various surfaces, which can damage the car if not appropriately handled. 

However, when you apply the necessary safety measures and use the correct pressure washer model, the chance of you damaging it is nonexistent. These are the most important dos and don’ts to keep in mind when pressure washing your car.

The dos of pressure washing a car

Use a pressure washer with enough PSI

PSI (pressure per square inch) is the amount of pressure the pressure washer can eject. Gas models can produce 2,000 to 2,800 PSI, while the electric models put out 1,300 to 1,700 PSI. So for cleaning a car, car valeting services in Liverpool recommend sticking to a model with around 1,500 PSI.

Stronger models can strip the paint, but when using moderate-strength pressure washers, it is entirely safe to use them on your vehicle.

Select a proper nozzle

Pressure washers usually come with a few nozzles suited for different types of jobs. For example, the lower-degree nozzles (such as the 0° or 15° ones) are used for spot-treating certain areas with stubborn stains. Although these are great for sturdier surfaces like concrete, they shouldn’t be used for cars as they can penetrate them.

When pressure washing a car, you should attach the 40° nozzle for cleaning the car’s body. You can switch it up to the 25° nozzle for cleaning the tires and wheels or the 65° attachment for applying soap.

Implement the safety measures

When using a pressure washer, you must keep safety measures in mind to avoid injuring yourself or anyone nearby. Firstly, you should apply safety gear, including goggles and non-slip footwear. You can also add earplugs, but they are optional, as gas pressure washers are much louder than electric ones.

Never point the hose toward other people or animals, and always keep a safe distance of 60 cm (2 feet) away from the object you are cleaning.

Thoroughly rinse the car

Always thoroughly rinse the car, as soap marks can leave blemishes and ruin its appearance. On top of that, they can be challenging to clean once they are completely dry. Of course, you can get rid of them with a clay bar, but a thorough rinse will prevent them from appearing in the first place.

The don’ts for pressure washing a car

Point the stream at a single spot for too long

Holding the stream at a single spot for too long can damage the surface, strip the paint, and cause marks. To avoid that, you should always clean from top to bottom, using sweeping horizontal strokes, unless you are using soap.

Use household cleaning products

You shouldn’t under any circumstances use household cleaning products like laundry detergent or hand soap. These can strip off the protective wax, which will cause the car to be a lot more prone to getting dirty, discolored, or oxidized. 

It is perfectly safe and even advisable to use detergent when cleaning a car to get better results, but always use a designated car detergent. In addition, when applying the detergent, attach the 65° nozzle, and apply it from the bottom up.

Pressure wash the engine

Technically, you can use a pressure washer to clean your engine, but it is far more complicated than cleaning the other parts. This is because there are numerous electrical components under the hood, such as spark plugs, alarm systems, alternator connections, and the like.

You can easily damage one or even multiple parts with a pressure washer. Hence, it would be best to leave that to professionals or carefully protect each piece with plastic bags (or something similar) before pressure washing the engine.

Dry on the sun

Letting the car air-dry in the sun isn’t the best idea since it can leave water spots. Apart from ruining its appearance, the spots can also damage the paint and cause etching. The etching occurs from the minerals and metals that the spots left behind, which can damage the paint. That is why you should always finish the job with a microfibre towel.

In summary

When done correctly, pressure washing your car is completely safe and will provide exceptional results. You might have been skeptical of using such a powerful tool on your vehicle’s exterior, but as long as you follow these tips, you will save a lot of money and time and keep it looking spotless.

John Robinson
John Robinson

Howdy! I’m John Robinson from Levittown, New York. I am a mechanical engineer for 15 years and already had an established car repair company. I developed a personal relationship with cars since I was a kid. I always love the sounds and smell emitted by a car or truck and even at construction machinery. Since then I have been married but my love for cars only grew.