pressure washer how to and troubleshooting guide
Tips & Tricks

Pressure Washer How-to & Troubleshooting Guide

Pressure washers are very helpful cleaning machines. When used properly, a functioning pressure washer makes cleaning various objects and surfaces much easier while reducing the time involved. However, similar to other power tools, pressure washers can develop issues now and then.

Common pressure washer problems are unloader valve issues, inconsistent pressure, starting issues, leakage issues, and pump and engine issues. Pressure washers are complex pieces of equipment that require routine maintenance, but most of these pressure washer problems are easy to fix.

This article will take you through the most common pressure washer issues and show you the best way to troubleshoot them.

How to set up and start a pressure washer

It’s important to know how to set up your pressure washer to ensure it works properly. Pressure washers vary depending on brand and models, but they all work the same. Follow the guide below to learn how to set up and start electric and gas pressure washers.

Setting up an electric pressure washer

Clean the water supply hose

  • Your electric pressure washer requires clean water to run properly, and often dirt and soil can get stuck inside the water supply hose.
  • Connect the water hose to an outdoor spigot, allow water to run through for about a minute, and flash out all the dirt.

Attach the water supply hose to the pressure washer

  • Locate the water inlet on your electric pressure washer, typically located at the back or on the side of the unit. Some models have a label saying “Inlet” for easy identification. If yours is not labeled, find an inlet with a thin screen that prevents dirt and particles from entering the pressure washer.
  • Once you find the inlet, ensure the garden hose has the type of threading that matches the one on the inlet. For example, some pressure washers have female threading on the inlet valve, while others have male threading.
  • Next, attach the water hose to the inlet and secure it with a screw if they match. Some models have different attachment mechanisms to secure the hose to the inlet.

Attach the high-pressure hose with the pressure washer

  • Pressure washers come with a high-pressure outlet hose made from reinforced materials that withstand highly pressurized water.
  • Find the outlet valve typically located at the front of the pressure washer unit. You may find the outlet valve beside the inlet valve connected to your garden hose in other models.
  • Place one end of the outlet hose on the outlet valve, pull back the valve with the hose positioned against it, then release the valve, and the hose will attach securely against the outlet. You will hear a slight click to indicate the outlet connection is secure.

Attach the spray gun to the high-pressure hose.

  • First, assemble the spray gun itself if it doesn’t come already assembled. Most spray guns come in two parts; the part with the trigger and the long wand.
  • Connect the back end of the wand to the front end of the spray gun and press them gently together while turning the wand clockwise to fit securely onto the spray gun. Some models do not have a wand, so that you can skip this step.
  • Take the free end of the high-pressure hose and connect it to the bottom of the spray gun. Make sure the connection is secure depending on the locking mechanism.

Connect the nozzle to the do the wand.

  • The nozzle attaches to the end of the wand or spray gun to adjust the pressure of your pressure washer. Both electric and gas-powered models have multiple nozzle attachments to produce different sprays for different jobs.
    • Red or zero-degree nozzle: This nozzle sprays the highest concentrated blast of water depending on the unit’s cleaning pressure. It is best for cleaning inside thin cracks between concrete. However, it can ruin delicate paint jobs and wooden surfaces.
    • Yellow or 15-degree nozzle: This nozzle produces a wider 15 degrees jet of water, making it best to remove stubborn stains from brick surfaces and concrete and unblock drains. You can also use it to remove paint without damaging the underlying layer. However, this jet is strong enough to damage wooden surfaces.
    • Green or 25-degree nozzle: This nozzle is excellent for most cleaning jobs since it has a decent amount of pressure to remove dirt and grime without ruining delicate surfaces.
    • White or 40-degree nozzle: This nozzle has the least pressure but covers a larger surface area. Although it is not powerful enough to get rid of sticky stains, you can use it to remove loose dirt and rinses. This nozzle is also excellent for extremely fragile surfaces like glass.
    • Black or 65-degree nozzle: You should use this nozzle with the detergent feature since it has the lowest pressure and can’t clean anything. It is ideal for releasing foam and detergent since it has the widest spray angle.
  • Place your desired nozzle at the front end of the spray gun, push it slightly in or twist it to fit securely onto the spray gun.

Add detergent to the detergent tank.

  • This is an optional step. Not all units come with an in-built detergent tank that holds detergent and allows you to spray water mixed with detergent.
  • Open the detergent tank and add your environmentally-friendly detergent. In other models, you can insert the siphon hose in a container with detergent and spray it from the nozzle.
  • As mentioned earlier, you should use the detergent function with a low-pressure nozzle to ensure optimal foam production.

Setting up a gas pressure washer.

Check the oil

  • If your pressure washer is not new, check the oil levels first. Then, take out the oil dipstick from the oil tank and check the levels. Refill the oil tank if the levels are low but don’t overfill as you might flood the engine.

Fill the fuel tank

  • Light duty pressure washers for residential cleaning use gasoline, while larger commercial models might use diesel fuel. Pour the gasoline inside the fuel tank while avoiding spillages are the tank.

Assemble the spray gun

  • Just like the electric pressure washer, the spray gun comes unassembled. Attach the wand to the spray gun and tighten it.
  • The gas-powered pressure washer also comes with various nozzles for different pressure levels. Attach your desired nozzle best suited for your cleaning project.

Connect the high-pressure hose

  • Attach one end of the high-pressure hose to the spray gun and the other to the high-pressure outlet. Make sure the connections are firm.

Connect the garden hose

  • Connect your garden hose to an outdoor water outlet and rinse any dirt and debris through it for about a minute. Allow all the water to flush out, then connect it to the pressure washer’s inlet.

How to use an electric pressure washer

Corded pressure washers require a power socket, while cordless pressure washers run on Lithium-ion batteries. However, their operating procedure is generally similar. Here’s how to start and use your electric pressure washer after setup.

  • Plug your electric pressure washer into a working GFCI(ground-fault circuit interrupter) power socket and turn on the socket. For the cordless models, insert the fully-charged batteries into the battery compartment of the washer.
  • Press the power button on the pressure washer unit to turn it on.
  • Without holding the spray gun too close, point it towards the object you want to clean and press the trigger.
  • Move the spray gun around the object until you’re satisfied with the results.
  • Then press the power button on the pressure washer to turn it off and unplug it from the socket.
  • Once it is off, press the trigger a couple of times for about 30 seconds to clear any remaining pressure inside the pressure washer pump. Leaving pressure inside the unit can damage the internal components.

How to use a gas-powered pressure washer

After setting up your gas pressure washer and making sure you have proper oil and fuel levels, here’s how to start it:

  • Turn on the water source and allow the hose to fill with water. Press the trigger on the spray gun to purge the system of excess air before starting the unit.
  • Switch the washer’s fuel valve to the “Open” or “On” position.
  • Move the choke to the “Open” position on the left.
  • Turn the throttle to “Full Throttle” or “Max” on the left side.
  • Turn the motor on.
  • Hold the gun firmly and squeeze the spray gun trigger to release pressure. Then, without releasing the trigger, pull the starter rope on the engine with the other hand.
  • Let the engine run for some seconds to warm up.
  • Move the choke to the “Close” or “Run” position and start using your gas pressure washer.
  • After pressure cleaning, turn the engine switch to the “Off” position, press the trigger to release any remaining pressure then turn off your water source.

Why is my pressure washer not spraying water?

If your pressure washer’s engine is running but not spraying water, there could be a clog in the wand, water supply hose, or inlet filter. Here’s how to fix the issue:

  • Check the water supply. Open the water supply spigot to full to ensure the pump has sufficient flow.
  • Start by disconnecting the water hose from the unit’s inlet and turning on the spigot. If water flows through the hose, then there is no blockage there.
  • Check the hose for kinks, breaks, or blockages if no water comes through. If running water through doesn’t clear the blockage, replace the hose.
  • Close the water source and reconnect the water hose to the pressure washer. If no water flows through, check the inlet filter for blockages. Remove and clean it or replace it if necessary. If the inlet filter is okay and the problem persists, continue troubleshooting.
  • Start the engine, attach the wand without a nozzle, and see if it works. If not, the wand is clogged or kinked. Using a cleaner wire, you can remove the blockage and then test if it works.
  • Try attaching the nozzle and press the trigger. If no water comes out, then the nozzle is damaged or blocked. You can also use a cleaner wire or paper clip to remove the particles blocking the nozzle. If it is too damaged, you will have to replace it.
  • If none of the above solutions work, you need to purge the system. Air bubbles in the system could be preventing water from cycling through. First, connect the garden hose to the pressure washer, turn on the faucet and press the trigger to flush water through the system without starting the engine. This clears the blocked pressure from the system and allows the pressure washer pump to work.

Why is my pressure washer not building pressure?

Low pressure is quite a common issue with pressure washers. Follow the troubleshooting guide below to get your pressure washer spraying with the appropriate force.

  • Check the throttle control position and move it to “Fast” to ensure the engine runs at full speed.
  • Ensure you have a high-pressure nozzle attached.
  • Check for a blocked water inlet screen. Disconnect the water hose from the water inlet and clean the filter screen and inlet to remove clogged dirt and particles. If the screen is damaged or too clogged, replace it with a new one.
  • Check if the high-pressure hose is leaking. Inspect the O-rings and if damaged, remove them with a flathead screwdriver and replace them with a new one.
  • Check for a blocked nozzle. Turn off the pressure washer engine and purge air out from the pump. Detach the spray tip from the nozzle extension and clean it with a wire tool to remove any stuck particles.
  • Check the pressure of the water supply. Use a pressure gauge to test the water supply flow rate. If the reading is less than 20 PSI and 4 GPM for 25 PSI and 7 GPM models, get an alternative water source with sufficient pressure and flow rate.
  • Check the power source. If you have a gas-powered pressure washer, refill the oil and if you have a cordless electric model, remove the batteries and recharge them. Reduced power will certainly reduce the water jet pressure.
  • Check for a faulty water pump. First, remove the high-pressure hose from the pressure washer and attach a regular garden hose to the outlet. Then turn on the water and the engine. The water flow should improve in pressure and length. But if this doesn’t happen, it indicates an internal pump issue. If the water pressure increases, there is a clog in the high-pressure hose, spray gun, wand, or nozzle.
  • Check for a damaged unloader valve. The main role of the unloader valve is to divert water flow in the pump into the by-pass when you’re not pressing the trigger. You can adjust the unloader valve to increase or decrease the pressure of the water jet, depending on the type of unloader valve (flow-actuated or pressure-actuated) you have. First, turn on the pressure washer and adjust the unloader valve in small increments to prevent building too much pressure. Attach a pressure gauge to the unloader during adjustment to monitor the changes in pressure and maintain it within the safe range. If the adjustments do not fix the water pressure, replace the unloader valve.

The pressure washer loses pressure when the trigger is pulled

There are various reasons why your pressure washer loses pressure when the trigger is pulled. Here are the reasons and how to fix them:

Water source

PSI(pressure) and GPM(water flow) provide the most efficient cleaning. So the water supply must be sufficient for your pressure washer to have the correct flow rate. Disconnect the water hose and check the water flow; if it’s slow or inadequate, you need to check your water pump.

Power source

If your pressure washer’s power supply is inadequate, it will cause low pressure when you pull the sprayer’s trigger. Check the oil and fuel tanks for your gas-powered washer; make sure you’re not using old oil or fuel. Then refill your unit if necessary.

If you’re using an electric pressure washer, check your power socket and ensure it is working. Check the breaker box for any tripped or blown fuses if the socket isn’t working. If you have a cordless pressure washer, you’ll have to recharge the batteries or replace them if necessary. Reduced charge will cause low water pressure.

Dirty or damaged nozzle

Nozzles clogged with dirt can cause little to no pressure when you pull the trigger. Using a damaged or the wrong nozzle can also be responsible. Check the nozzle and make sure you’re using the right one. First, inspect the nozzle for any dirt and particles and try cleaning it with a wire cleaner. If cleaning the nozzle doesn’t work, replace it with a new one.

Restricted unloader

The unloader’s work is to prevent water wastage by sending water through the by-pass when you’re not using a pressure washer. However, it also controls the pressure on the nozzle. Therefore if the water jets are not coming out at the right pressure, the unloader could be clogged with dirt or damaged. In this case, take out the unloader from the washer, and clean it with a wire brush. Inspect it and check for kinks or cracks and replace it if necessary.

Dirty or damaged piston

The piston is your pressure washer that helps maintain water flow. However, the piston cannot work properly if its movement is restricted. Also, the piston wears out over time and becomes ineffective at pressurizing water, resulting in a weak water jet. The solution is to remove it from the pressure washer with a screwdriver or wrench and clean it. If cleaning doesn’t help, replace it.

Improper pressure washer valve settings

The water pressure from your pressure washer also depends on the proper settings of the unloader valve for the desired water flow. Setting the unloader valve to high pressure can cause the engine to stall, causing low water pressure. To fix this, consult a professional to help adjust the unloader valve.

Clogged or worn-out O-ring

The O-rings in pressure washers deteriorate over time, causing water leaks and loss of optimum water pressure. Remove the O-rings and replace them regularly.

What does the unloader do on a pressure washer?

There are two types of unloader valves; trapped pressure unloader valve or flow actuated unloader valve. Both types are activated by the increase in pressure or decreased inflow.

When water stops flowing from the nozzle, the unloader valve, situated above the water inlet, uses its spring and back-check mechanism to divert the pressurized water into a by-pass by cycling it from the outlet side of the pump to the inlet side. This process helps reduce the pressure of the water and prevents it from building up while the pressure washer is idling. The unloader valve switches off and redirects the water to the nozzle when you pressure the trigger again.

An unloader valve is technically a safety switch or relief valve for your pressure washer. It allows you to put your pressure washer aside without switching it off safely. Without the unloader valve, the water pressure in your machine will continue to build up in the nozzle when it’s idling and potentially damage your pressure washer’s pump.

Additionally, the unloader valve allows you to adjust the cleaning pressure of the spray gun without changing the nozzle.

Although the unloader valve prevents dangerous pressure build-up, the by-pass mode can also be dangerous. During by-pass mode, the pump components move and create friction and heat, which transfers to the water flow. This heat can increase dangerous temperatures since no cold water enters the pump during by-pass.

Therefore we advise you to avoid putting your machine on by-pass mode for longer than two to three minutes to prevent overheating and eventually damaging your pump. Squeezing the trigger will interrupt by-pass mode and allow cool water to flow through the system, or you can also switch off your pressure washer and purge the system.

Pressure washer unloader valve symptoms

It’s important to know when the unloader valve in your pressure washer fails, as it will put the pump at risk of damage. Symptoms of a bad unloader valve are easy to detect since they will immediately impact your pump’s performance. There are three main indicators of a defective unloader valve:

  • Reduced flow and pressure at the nozzle after pressing the trigger. A damaged or clogged unloader valve can get stuck in by-pass mode, thus preventing water from leaving the pump and entering the outlet hose and nozzle.
  • Excessive pressure at the spray wand. A damaged or misaligned unloader valve can also cause pressure to build up above the maximum pressure for safe functionality.
  • The pump in the gas-powered pressure washer will start stalling when you put the machine on idle. This is because the damaged valve causes accumulated pressure which locks the pump’s internal components and prevents rotation of the engine shaft.
  • The thermal release valve opens and releases steam water from the pump. This happens when the unloader valve clogs or sticks shut.
  • Excessive load on the pressure washer’s engine or engine.
  • Overheating pressure washer pump.

How do you clean an unloader valve?

The unloader valve is highly sensitive to the particles and dirt in the water supply. These particles accumulate in the valve and cause the valve to get stuck, allowing more water to be by-passed, causing reduced flow through the nozzle. Cleaning the unloader valve will help free it and allow smooth functioning. Follow the step-by-step guide to remove dirt from your stuck unloader valve.

  • Remove the spark plug wire off the spark plug on the pressure washer engine to avoid accidental start-ups.
  • Take out the retaining pin above the unloader valve by putting the screwdriver under the pin and listing it upwards and outwards.
  • Remove the unloader valve using an open-end wrench by turning the valve counterclockwise.
  • In other pressure models, you can use a screwdriver by putting it behind the spring and gently moving it outwards, and it should pop out from its socket.
  • Inspect the valve and ensure both the small and long pins are removed freely. If either pin is stuck, clean it with a wire brush.
  • Use a pin to get rid of particles stuck in the pore below the spring.
  • Apply grease on the O-rings to reduce friction during movement.
  • Then reassemble the unloader valve in reverse. Once you put the valve back into its place, hit it gently with a screwdriver or wrench to secure it, then return its retaining pin.

Electric pressure washer motor won’t start.

If your electric pressure washer won’t start, there are several things you should check. Follow the guide below to know all the possible causes and how to fix them.

The outlet has no power.

An electric pressure washer runs on electricity; anything that interrupts power flow prevents the machine from starting. So first, check the condition of the power outlet by plugging the washer’s power cord into a different outlet. If that pressure washer starts, there’s an issue with the first outlet. If it is a GFCI, you can easily replace it; otherwise, you can replace it.

There is a circuit issue if the pressure washer doesn’t start on the second outlet. Go to your electrical panel and look for a tripped breaker or a blown fuse. Reset the tripped breaker or replace any blown fuse.

Tripped GFCI on the power cord

Plug the power cord into a working power socket and press the reset button on the GFCI. If it doesn’t reset, check for physical damage on the power cord.

Power cord issues

Check the power cord if there is no circuit issue and other appliances are working on the outlets.

  • First, ensure that your cord is longer than 25 feet and a 12-gauge wire. Lighter-gauge cords will not provide adequate power to the pressure washer.
  • Then inspect the cord for any fraying or damage and replace the cord if necessary.
  • Check the connections on the cord and ensure the electrical plug ground connection is firmly connected.

Power surge in the circuit

If the circuit isn’t powerful enough, the electric pressure washer won’t start. Connect a multimeter to the outlet socket you use with your machine and test the amperage. If the reading is below the recommended amperage for your pressure washer, the circuit needs more power, or you’ll need a less powerful pressure washer. You have to consult an electrician to fix the power issues.

Alternatively, you can reduce the power usage in your home by disconnecting high-powered appliances you’re not currently using, such as washing machines and dishwashers.

Failed capacitor

Start capacitors are electrical devices that give the motor the extra push to start running. So if the start capacitor fails, the pressure washer’s motor won’t start. You can know the capacitor has failed when the motor doesn’t start, but you can hear a humming sound. So take out the capacitor, test for continuity with a multimeter, and replace it if necessary.

Tripped thermal overload on the motor

First, allow the pressure washer motor to cool down, and press the overload reset button. If the thermal overload doesn’t reset, wait a while longer and try resetting it again. If nothing works, the motor is too damaged and needs replacing. You can contact the manufacturer for a replacement if it is still under warranty.

Failure to prime the pressure washer

Air will often get trapped in your pressure washer, preventing the unit from starting or causing low pressure. The solution is to prime your pressure washer. Here’s how to do it;

  • Connect the water supply hose to the inlet on your pressure washer.
  • Ensure the pressure washer is off.
  • Press the trigger and let the water flush the air out of the system for at least a minute.
  • If you notice pulsing pressure, clean the nozzle. Take out the nozzle from the wand and soak it in vinegar solution, then loosen the clogged particles with a pin or needle.

Pressure washer is surging.

Surging happens when the water pressure is okay, and then it reduces. There are reasons why your pressure washer is surging, so you have to use the elimination process to identify the source of the issue and fix it.


A partially clogged nozzle will cause pulsating or weakened water pressure. So use a nozzle cleaning kit to clean your pressure washer nozzle. If cleaning doesn’t help or it is kinked, replace it.


If the unloader is worn out or blocked, it will restrict water flow through the nozzle. You will have to take the unloader out and clean it. If it is damaged, replace it.

You can also adjust the unloader valve settings in small increments to increase the washer’s pressure.

Water supply hose and filter

If the water supply hose is okay, ensure it is at least three-quarters of an inch or bigger to avoid surging. If your water hose is the correct size and surging continues, inspect the inlet hose for any blockages or leaking water. If cleaning the house doesn’t remove the blockage, replace it.

Also, check the inlet filter that prevents dirt and debris from passing through the system. Over time dirt will accumulate and restrict sufficient water flow.

Air trapped in the system could also cause surging. Release the air by turning off the pressure washer and pressing the trigger. The water will flow through the system while pushing the trapped air out.

Water supply and pump

If insufficient water is coming out of the water source, then your pressure washer is likely to start surging. If your water supply is okay, check the pump for worn packings and replace them.


Check the inlet and outlet valves. The inlet valve allows water into the pressure water while the outlet valve releases pressurized water into the high-pressure hose. Inspect the valves and clean or replace them as necessary.

If the valves are okay, check the valve springs. It could be broken or lack proper tension and needs replacement.

Pressure washer is not siphoning detergent.

If your pressure washer is not dispensing the detergent, here are the reasons and how to fix them.

Using the wrong nozzle type

The most common reason your pressure washer is not siphoning detergent from its tank is using the wrong nozzle. The soap dispenser uses the black nozzle with the widest angle since it generates low-pressure jets.

Using a high-pressure nozzle will cause an increased build-up of the backpressure of the flowing water, thus preventing the detergent’s suction. Instead, inspect the nozzle and replace it with a low-pressure nozzle which will lower the output pressure and allow the washer to pull up the detergent.

Blocked siphon tube

A blocked siphon tube will prevent detergent from flowing through it. Check the tube and clean it thoroughly using a wire. To prevent future blockages, you can install a chemical filter to prevent dirt from passing through the tube and causing clogging.

Improper detergent hose connection

Check the soap injector is placed correctly. Attaching the injector to the position will prevent water from flowing correctly through the injector.

Inlet pressure is too high.

The detergent injector will not work if the inlet water pressure is too high. Instead, try closing the water supply valve slowly while pressing the trigger until soap suds are visible.

Faulty metal ball

There is a ball inside the soap injector assembly that can get stuck due to poor maintenance—the ball and spring work to control siphoning of the detergent. When the pressure washer is on high pressure, it overcomes the spring resistance and seals the ball against the O-ring, preventing water from entering the detergent tube.

The spring pushes the ball away when the pressure reduces and allows the water to mix with the detergent. Over time the spring wears down and causes the metal ball to get stuck on the O-ring. The detergent will not come out even when operating on low pressure. The solution is to take out the spring and ball, clean them, put grease on the ball and O-ring, replace the spring and reassemble the injector.

Pressure washer is not staying on.

There are a number of reasons why your pressure washer will not stay on. Some reasons are mechanical such as carburetor issues, while others are improper use, such as not priming the machine.

Check the basics

Before starting the troubleshooting process, ensure you haven’t missed any basic steps below. Ensure;

The electric pressure washer is plugged in, or the gas-powered pressure washer has enough gas and oil.

  • Power switch is on
  • Connected to a working water source, and the faucet is on
  • There are no bends or leaks in the water supply hose

Electrical pressure washer

Here’s how to fix an electric pressure washer that won’t stay on:

Check the power cord and outlet

Check your pressure washer’s extension cord. A break or kink on the cord could be affecting current continuity, causing the machine to keep going on and off. If the cord is damaged, replace it.

If the cord is fine, check the socket. Plug in another electrical appliance like a lamp to test the power outlet. If the lamp has the same issue, there is a circuit problem. Ensure there is no fault when you move the plug or cable. A loose connection to the pressure washer or the plug on the power outlet can prevent the washer from staying on.

If your pressure washer uses a GFCI (ground-fault circuit interrupter) plug, check if it’s working. They often break down. The pressure washer machine should be okay if you get a green light on the plug.

Check the unloader valve.

The unloader valve maintains the water to stay under pressure when the pressure washer is idling so that the spray has consistent pressure the next time you press the trigger. Therefore, a bad unloader valve can cause the engine to stall due to pressure inside the pump building up more than the engine’s power to rotate your pump. As a result, your pressure washer will start turning on and off. We recommend replacing your unloader valve to stop the issue.

Gas-powered pressure washer

Here’s how to troubleshoot a gas-powered pressure washer that keeps going off and on.

Winterize the gas pressure washer

Like other gas-powered tools, the gas pressure washer requires winterizing when it sits idle during winter to avoid damage. Winterizing your pressure washer involves ensuring all tanks and hoses are empty of oil, gas, water, and detergents.

When water freezes in the system, it expands and causes breaks, leading to leakages in the hoses and tanks. Draining the oil and fuel is equally important since gas breaks down over time; it evaporates and leaves behind a sticky residue. This thick residue can clog your washer’s internal pipes and carburetor.

Check the spark plug.

A failing spark plug will not produce a consistent spark to ignite the fuel in the engine, causing the engine to shut down intermittently. Take out the spark plug and visually inspect it for cracks and heavy carbon build-up. There is also a special tool that tests if the spark plug is defective. If there is no strong spark between the tester’s terminals, replace the spark plug and ensure all connections are secure.

Check the ignition coil.

If the spark plug is fine, there could be an issue with the ignition coil. The ignition coil transfers current to the spark plug while the engine runs. A faulty ignition coil will prevent the pressure washer from starting or staying on. Use an ignition coil tester to check the ignition coil and replace it if necessary.

Check the carburetor

If you just took your pressure washer from storage and you had not winterized it, there’s a good chance the carburetor is clogged with stale fuel. Fuel breaks down over time, evaporates, and leaves a sticky substance that clogs the carburetor and causes ignition issues.

If you notice the residue, use a carburetor cleaner to clean the carburetor. If cleaning doesn’t work, you have to rebuild or replace the entire carburetor. For preventive measures, do not use gas that is more than 30 days old to run your pressure washer.

If there is no clogging, the carburetor could be too old. The carburetor is responsible for controlling the ratio of fuel and air for ignition. So if it is too old, it will not work efficiently, causing the washer to keep going off during operation.

Prime the pump

Air bubbles trapped in the pump can cause the washer to work intermittently. Therefore, it’s important to prime your washer after and before every use.

How to use soap with a pressure washer

The high-pressurized water from the pressure washer is enough to lift tough stains and clean large surfaces. But some models come with detergent injectors which can help improve cleaning performance and remove much tougher stains.

We recommend using biodegradable soap, especially when cleaning objects and surfaces outside, to avoid contaminating the soil and plants. It’s also important to choose a detergent suitable for your cleaning project; for instance, you cant use concrete cleaner for your car. With your pressure washer detergent in hand, follow the general guide below to learn how to use soap with your pressure washer.

  • Perform a general inspection of your pressure washer to ensure the soap injector works well. Ensure the water supply hose delivers water at the appropriate pressure and has no kinks or leaks. Check the detergent hose and clean it to remove dirt and debris.
  • Fill the detergent tank with water and add the appropriate amount of soap according to the manufacturer’s instructions. The general rule for the solution is 1/3rd soap and 2/3rd water, but some soaps brands require a solution of equal parts of water and soap.
  • Close the soap tank and turn the nozzle switch to “On” to draw the soap into the pressure washer pump while spraying.
  • Choose the right nozzle for using soap. Attach a low-pressure nozzle when using the soap injector. The soap injector works by constricting the flowing stream of water through the nozzle so that it can draw water from the soap reservoir through suction.
  • The narrow stream increases the water’s flowing velocity and reduces its pressure to pull the soap towards the vacuum suction.
  • If you use a high-pressure nozzle, the high pressure will block the vacuum and prevent the injector from drawing the soap solution into the pump. Instead, more water will flow into the soap tank.
  • Press the trigger, and the pressure washer will produce low-pressure water mixed with soap.
  • Spray your detergent upward while overlapping each pass a little to prevent streaking and uncovered patches.
  • After applying the detergent, allow it to sit on the surface for about 10-15 minutes to lift the stains, grime, and oils. To prevent it from drying, you may have to reapply the detergent on the surface on sunny or windy days.
  • Remove the low-pressure nozzle and attach a high-pressure one. Now press the trigger and rinse the surface by moving the nozzle up and down.

Never use detergents and soaps with bleach in your power washer because bleach is corrosive and will damage the washer pump.

How to change pressure washer nozzles?

A pressure washer’s PSI and GPM almost don’t matter without the appropriate nozzle. The nozzle is the device at the end of the wand that creates the pressure required for pressure cleaning. The locking mechanism of the nozzle onto the wand may vary depending on the brand, but the basic procedure is the same. After choosing your desired nozzle, here’s how to change them:

  • Switch off your pressure washer using the power dial or button.
  • Without touching the colored nozzle tip, pull down the retainer, and the nozzle should detach.
  • Pull back the retainer and insert the new nozzle to install a new nozzle.
  • Then release the retainer to secure the new nozzle onto the wand.

For other models, you have to;

  • Switch off the pressure washer.
  • Hold the tip of the nozzle and turn it counterclockwise, and it will detach from the wand.
  • Insert the new nozzle into the wand and turn it clockwise, and it will lock into place.

How much PSI does a pressure washer generate?

All pressure washers do not produce the same amount of pressure. Therefore, they are categorized depending on their pressure(PSI). Different surfaces require different PSIs, meaning you will choose your pressure washer’s PSI depending on your cleaning project. This will also determine the type of pressure washer you choose; gas or electric.

Generally, gas pressure washers have more power and are best for residential and industrial purposes. In contrast, electric pressure washers have lower power and are best for residential cleaning. Here are the pressure washer categories and their PSI ratings.

1. Light duty 1000 – 1900 PSI

These pressure washers are great for regular maintenance and light household cleaning jobs such as cleaning automotive, furniture, and wood floors. These models are usually hand-held electric models.

2. Medium duty 2000 – 2800 PSI

These pressure washers are excellent for slightly heavier residential cleaning tasks such as cleaning concrete floors, wood surfaces, and grills and removing oil and grease stains.

3. Heavy-duty 2900-3200 PSI

These are commercial-grade pressure washers that run on either gas or diesel. These washers are powerful enough for mold and mildew removal and cleaning multi-story buildings. You cal also use these pressure washers to clean sidewalks and driveways.

4. Extra heavy-duty 3000 and higher PSI

These are great for industrial cleaning, heavily stained concrete surfaces, stripping off paint from all surfaces, large-scale cleaning, and graffiti removal.

How do you know if your pressure washer pump is bad?

The pressure washer pump is a high maintenance component due to its vital function in the performance of a pressure washer. Unfortunately, this also means without proper care, pump repairs can be quite expensive. Unfortunately, pump issues are difficult to diagnose because most symptoms can be due to other problems. If you notice any signs that indicate a bad pressure washer pump, stop using the machine immediately and consult a professional to avoid further damage.

  •  Below are signs of a bad pressure washer pump:
  • Reduced pressure from the pressure washer. This occurs due to a worn-out O-ring or rubber gasket, which seals the inside of the pistons and valves in the pump.
  • Pulsating output pressure due to insufficient inlet water supply.
  • Leakage around the cylinder head or on the inlet or outlet elbow is caused by frozen water inside the pump.
  • Engine stalling caused the pressure washer to keep going on and off.
  • Sputtering sounds from the pump due to a failing unloader valve caused by increased pressure in the pump.
  • Overheating pump due to excess pressure build-up in the pump during by-pass mode.

How do I know if my pressure washer gun is bad?

The pressure washer gun gives you the grip for the comfortable operation of the pressure washer. Various signs will show a faulty pressure washer gun. They include;

  • Reduced water jet pressure due to blockage or kinks on the trigger gun.
  • Not water when your press the trigger.
  • Pulsating pressure from the nozzle.

How do I check the pressure on my pressure washer?

The pump in a pressure washer gives the machine a fixed pressure through the nozzle, but you can use the unloader valve to adjust this pressure. So the best way to determine your pressure washer’s pressure is by using a pressure washer gauge. It measures the pressure levels of the pump while also indicating problems with damaged components or leakages in the pump.

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Use the quick connect fittings to install the pressure washer gauge at the closest point on the outlet side of your pump to get the pressure measurement independent of the length of the outlet hose and pressure drop in the hose.


If you pressure wash often, you’re bound to troubleshoot some issues once in a while. Thankfully, our guide will help you troubleshoot the most common pressure washer issues. Whether that involves electric models, gas-powered models, blockages, water pressure, leakages, or others, you have confidence in setting up and fixing your pressure washer. When in doubt, contact the manufacturer or professional to help fix the issue.