Keeping a car clean is the least we could do, given how much money they cost us.
However, despite the will to keep a car clean, many people neglect washing the engine due to its intricacies.
Engine cleaning is typically left to the professionals to avoid damaging it, but how much harm can a car wash do to your engine?
Quick Answer
An engine isn’t waterproof and can incur severe damage in a car wash if washed incorrectly. Coldwater on a hot engine block can cause it to warp, exposing wires and sensors can lead to their malfunctioning, and a wet intake system can cause far more severe damage.
Read on as we take a deeper dive into how washing your engine can cause it to suffer damage.
We will also discuss the proper way to clean your engine, aside from the benefits that come with keeping it spotless.
Can a Car Wash Damage Your Engine?
As much as we want to pamper our car with a good engine wash, water and engines don’t exactly make a great combination.
Quick Answer
A car wash can damage your engine since many engine components are sensitive to water. Exposing these parts to water can cause them to stop working. Modern automobiles sport better-insulated engine parts, making them less vulnerable to water damage. However, such parts are not 100% water-proof.
It pays to know which parts are the most susceptible to damage and how they can affect your car’s performance.
How Water Can Damage the Engine’s Cylinder Head
Adding water to a hot engine is a recipe for disaster. Metal parts like your car’s cylinder head can experience thermal shock due to a sudden shift in temperature.
This reaction causes tension within the metals and could cause them to warp, crack or break.
A cylinder head is essentially the engine’s armored suit; it keeps all the internal components and fluids in place.
If a cylinder head is damaged, any of the following may occur:
How Water Can Damage Your Car’s Electrical System
Cars now have more electrical systems than ever, many of which reside under the hood.
For these electrical systems to be functional, car manufacturers can only make them water-tight to a certain extent.
Many plumbing materials use copper, and according to a study done by ScienceDirect, the amount of copper in water affects its corrosion rate.
Quick Answer
Generally speaking, water and electricity do not mix because this can cause premature corrosion, aside from a short circuit. Due to water contamination, parts like the fuse box, onboard computer, and other electrical modules may experience electrical shorts.

Removing the car’s battery can prevent short circuits, but that doesn’t safeguard all the car’s electrical components from damage.
Below are other electrical components under the hood that can be compromised by exposure to water:
The Effects of Water on Your Car’s Intake System
A car’s intake system is composed of an air filter, mass flow sensor, and throttle body.
It is responsible for sucking in air to be mixed with fuel and compressed as part of the combustion process.
If a substantial amount of water manages to make its way to your car’s intake system, the water will not be compressed and will result in a pressure build-up that can bend your piston rods and crack your engine block.
Is Washing Your Car Engine Bad?
Quick Answer
Washing your car engine can be risky but only if you don’t take proper care when doing so. All things considered, it is far more advantageous to clean your car’s engine on a regular basis instead of leaving it dirty.

Keeping your car’s engine clean has the following benefits:
What To Do if a Carwash Has Damaged Your Engine
After having your car cleaned at a carwash, it is always a good idea to inspect it for any damage.
However, water damage to your engine may not always be visible, so you should let the car run idle for a few minutes before leaving the establishment.
Aside from giving your engine bay a visual inspection to check for any physical damage, do the following:
If the car still fails to run normally, take the following action:
Note that in case your car suffers damage, you will need to establish that the damage was done intentionally or through the carwash establishment’s negligence.
Legal fees can cost more than the actual damage in most cases, so it is best to settle claims through insurance.
Key Takeaways
Although engines in modern cars are better insulated, you can’t discount the risk of them incurring water damage.
The good news is, as long as whoever is washing it takes proper caution, the chances of any damage are very minimal.
In fact, keeping an engine dirty is far more detrimental than washing it now and then. Thus:
Sources
Fix Auto USA: Do Car Engines Need to Be Cleaned?
Car and Driver: How to Clean Your Car’s Engine
Kenny’s Auto Detail: Benefits of Engine Steam Cleaning.
South Florida Sun Sentinel: Driving through puddles can kill your car
VEHQ: Can You Wash An Engine While It’s Hot?
Clearwater Cylinder Head, Inc.: How to Tell if Your Cylinder Head is Bad
It Still Runs: What Happens With Water Damage in a Car?
Protect My Car: Can Water Damage Your Car’s Alternator?.
Answers To All: What happens when distributor cap gets wet?
sgCarMart: Understanding a car air intake system
Hensley Legal Group: Who is Liable if My Car is Damaged at a Car Wash?
WashTec: Damage to a vehicle caused by a car wash – But who is liable?
https://shinycarproject.com/why-does-my-car-smoke-after-a-car-wash/
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