What To Do If You Drove Through Water And Car Won’t Start?

A question is usually asked, “what do you do if you drove through water and car won’t start.” Driving across the water, particularly deep water, may be risky.

It can take your automobile away or harm the engine. Additionally, there may be something beneath which might damage the vehicle.

Some automobiles can keep running, while many won’t. There are a variety of explanations for why your car died after driving through water.

Determining why your automobile won’t start without inspecting it isn’t easy. Below are some possible reasons you should consider.

Why After You Drove Through Water And Car Won’t Start?

drove through water and car won't start
Drove Through Water And Car Won’t Start

Several things may go bad based on how deep the water is and how users drive across it.

Yet, the following are the most prevalent causes why your car won’t start after driving through water.

Dead Battery

Electrical equipment and water are not friendly to each other. They must be held far apart from one another. Drivers could have harmed the battery by driving through the water.

Possessing a dead battery upon driving over water is a common problem that those who travel across puddles experience.

A dead battery will cause the car not to start or start slowly. Yet, there may be further faults that prevent your automobile from starting.

Malfunctioning Catalytic Converter

It would help if you inspected the depth of the water where you drove the vehicle through. It is not good when the water is deep, and you are going and pushing the gas pedal hard.

It may enter the exhaust pipe and harm the catalytic converter. It is one of the main reasons you drove through a puddle and now car won’t start.

Damaged Electrical Components

Electrical issues are prevalent when traveling across the water. You can think of this problem, especially when the water is not that deep, and the automobile won’t ignite after passing a puddle.

The problem might be malfunctioning electronic parts.

Many electrical connections in certain automobiles are located in a very low position. They could be broken even though driving through shallow water.

Water In The Fuel System 

When the car doesn’t operate following running over water, it might be due to water getting into the fuel system.

Even passing over a small amount of water can cause it to penetrate the tailpipe or fill the cylinders.

When this occurs, the pistons cannot compress the air as effectively as they used to. As a result, you’ll experience a hydro lock problem, and the automobile will not start.

When left unchecked, it will create considerable damage to the engine.

If you continue attempting to ignite the car in this state, you risk damaging the connecting rod. It will cause more significant engine damage.

Damaged Head Gasket 

In case the water was extremely deep, and the vehicle stopped after driving into it, the water might have seeped into the head gasket.

Water can destroy it easily. The valves themselves might be damaged.

What Should I Do If My Car Doesn’t Start After Driving Through Water? 

Some automobiles will keep running despite moving via water; however, most won’t. Should you encounter this circumstance, use these steps to make your car operate again.

Also, the below will show you how to check if water has entered engine.

Check Your Car’s Interior

After you drive through wet conditions, some water may enter the cabin. It may cause damage to the internal parts of your vehicle.

Inspect the carpet and floor surface elements to see whether they are wet.

Once the car’s interior is damp, you must remove the water using a wet-dry or wet vacuum. Users can also utilize the automotive vacuum cleaner with a fan. It can help your automobile dry quickly.

Absorbing the water with fabric or towels is another possible way. You need to change the carpet in the automobile with a drier one.

Then, take out the water via the drain holes, usually at the bottom of the car doors. Besides, circulate the interior of your vehicle with air.

Once draining the water, keep the doors and windows open to allow sunlight and air in. When your car got wet inside and won’t start, you need to give it some time to dry.

You should also install a table or standing fan inside your vehicle in advance. Uninstall the seats and allow them to dry —they will dry quicker.

Check Your Air Filter

Examine the air filter for wetness or symptoms of moisture. If this is the case, find a replacement. You could also be required to change the engine oil.

Check Your Fluids

Water will penetrate the engine bay and pollute vehicle fluids, including engine oil, differential fluids, and transmission oil while traveling across the water.

Assess the state of the fluids with a dipstick. They appear in any symptoms, including discolored, diluted, or milky conditions.

It means they are polluted. You need to get your vehicle inspected by a professional since tainted fluid might cause engine harm.

Check The Underside Of Your Vehicle 

Inspect the underneath of your vehicle for trash, grass, and dirt. Look at the engine bay, undercarriage, and bumpers as well.

Check The Suspension And Brake Joints 

Dirt and mud may enter the braking systems as driving into water, affecting the operation of your vehicle.

You might want to double-check your lights when you’ve completed these tests. In addition, ensure that all faulty parts are changed when they can’t be fixed.

Braking components are not something you can neglect, as it is highly related to your family’s safety.

What To Do if Your Car Stops Because of Water

car won't start after driving through water
Car Stops Because of Water You Need To Do

When your car stops because of water, don’t panic. There are some ways to reduce the damage. If lucky, your engine may start again. Here is what you should do in that situation.

Cranking The Engine 

To begin, you can crank to force the water from the cylinders and pistons of the engine with your hand. It will help the fuel system avoid unwanted damage.

As you do that, you can use the starter to accomplish the job quicker and remove all the water in the cylinders.

Check the engine oil and empty it in the event of any unusual impurities like chocolate milk.

It is advisable to give some time for the electrical equipment to dry before attempting to restart your vehicle.

Draining The Vehicle’s Fuel System

Suppose the engine is filled with water; the fuel system most likely contains some. You should drain a little gas from the tank’s bottom.

You should carefully inspect the drained fuel to see whether it is a combination of oil and water. If yes, it is advisable to empty the car’s fuel system.

You can’t ignite or continue the automobile to use all the petrol at this stage. Here is the way for you to do the task. The method, as some prefer, is called Siphon Tube Method.

First, put the tube from the siphon pump in the fuel tank. For that, open the gasoline filler valve and remove the cap.

After that, add one tube end via the filler neck. Continue doing it until it reaches the bottom of the tank.

Should the vehicle have a metal door that could block the tube from entering the tank, or use a screwdriver to unlock the door carefully? Continue to push the tube down.

Following that, clean any spilled fuel using a cloth. Pump the gasoline. To do so, insert the other tube end in the external tank and use the manual pump to transport the fuel to the tube.

Continue pumping till the gas is completely drained. 

Ensure that the pumped gasoline is appropriately disposed of. If you are unsure and unwilling to do it, contacting a waste disposal center or a car service is your option.

Replaced Damaged Parts 

The first step is to check if any electronic parts get water. If you suspect this, take the automobile to a repair to determine which systems are damaged.

Many elements will likely be broken, and repairing or replacing them would be expensive.

Since these components have been ruined by water, there’s a high likelihood you cannot fix them and will need to replace many.

The dead battery is an example. You’ll have to purchase a new battery. Replace the battery with precaution since the water within the battery might lead it to malfunction.

It could also electrocute you. Besides, once the car’s catalytic converter and head gaskets have failed, you must replace them.

What To Do if Caught In A Flood?

Passing over deep water will certainly damage your car. However, what if you become stuck in the street with a flood? It’s critical to be calm when your automobile stalls and locks you.

In an emergency, like when your car stopped in flood water, you should escape the car and seek higher land.

In case the car is entirely flooded, you must remain calm and take a breath. Avoid opening the car immediately, as it only allows water to enter.

You should wait for the water to fill the car a bit until the pressure in the interior and outside balances. It will help you open the door properly.

When the water flows, find a safe place to wait for help. If you’re not being carried along, your automobile’s roof is a good place to be.

You should only assess the damage once the water has retreated.

How Much Is Water Too Much To Drive Through? 

water in engine fix
How Much Amount Of Water To You Drive Through

You avoid attempting to drive across water whose depth you do not know. Generally, a few inches of water in potholes are acceptable. You should slow down the car to maintain control.

Even when driving at enough speed, a few inches of water might cause you to slip. When the depth of the water reaches 6 inches, it is enough to cause the car to lose control.

No matter how fast you are, hydroplaning may happen with the water depth from 1/10 inch.

A 3,000-pound (1360 kg) car, the common weight of most automobiles, can normally float in two feet of water. The car’s height could also influence how easily the engine might flood.

Vehicles with different heights can withstand different water areas.

You’d better avoid areas with water that can reach the door frame. Water entering the door frame can flood the intake system and the engine compartment.


The above are reasons and solutions for you if you drove through water and car won’t start.

Damp spark plugs, an electrical connection in the starting system, damaged battery, and catalytic converter frequently cause it.

If you are unsure what is wrong, you should take the car to a technician for a thorough inspection.

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