While they are our best companions for keeping our patios and driveways clean, pressure washers can also be a source of frustration. One such instance is when your machine can’t run unless the choke is engaged. So, what could be the reason your pressure washer only runs on choke?
A pressure washer running only on choke can be due to a clogged carburetor, air leak, use of wrong fuel, faulty spark plug, or defective fuel line. Either of these reasons will cause the engine to function abnormally, often stalling or refusing to start. Always identify the source of your pressure washer’s problem before taking corrective action.
Pressure washers go a long way to boost our efforts in keeping our spaces clean. However, they can also give us a run for our money when they develop technical problems. A pressure washer that can only run on choke is a case in point. And if that’s what you’re experiencing, this article is for you.
What is Choke?
A choke is a valve or plate that restricts air intake in an internal combustion engine. It’s usually located near the carburetor and is operated by a lever on the dash or steering column. The choke’s primary purpose is to enrich the fuel-air mixture in the engine cylinders during cold starts.
When the engine is cold, the choke closes to allow less air so more fuel can be drawn into the cylinders. The enriched mixture makes for easier starting and prevents the engine from stalling. Once the engine warms up, the choke is opened to allow more air into the cylinders for regular combustion.
So, you can think of choke as a kind of “gas pedal” for a cold engine. The less air allowed in, the more fuel is drawn into the cylinders.
Reasons Why Pressure Washer Only Runs On Choke
We’ve several reasons why your pressure washer only runs on choke. It could have something to do with the carburetor, the fuel, the air filter, the spark plug, or other engine parts. Identify and fix this problem immediately to get your machine working again and minimize the risk of damaging the engine.
Some of the potential reasons behind a pressure washer that only runs on choke include:
1. Clogged Carburetor
If you’ve noticed that your pressure washer stalls every time you turn off the choke, it’s likely because there’s something wrong with the carburetor. Perhaps you have a defective or clogged carburetor that needs cleaning.
You see, over time, dirt and debris can build up and clog the jets in the carburetor. When this happens, the carburetor won’t be able to get enough gas and will cause the engine to starve. The engine will then stall when you try to turn off the choke.
Sometimes, the carburetor clogs can emanate from keeping fuel in the pressure tank for too long. When stored for long, some ingredients in fuel will evaporate, leaving back a thick, gummy substance that can clog the carburetor jets.
How to Fix:
If you think your carburetor might be the issue, you can try cleaning the jets yourself. A simple blow out with compressed air should do the trick. If that doesn’t work, you might need to take it to a professional for a more thorough cleaning.
2. Fuel Issues
We’ve all at some point struggled with the question, “what happens to the engine when you use the wrong fuel type?” Well, if you’ve been using the wrong fuel in your pressure washer, that could be why it’s only running on choke.
For example, if you’ve been using ethanol-based fuel in your pressure washer, that could be the problem. Ethanol-based fuel tends to attract moisture. And as we all know, water and engines don’t mix.
As such, it’s best to stick to the ideal fuel for your pressure washer. Usually, the appropriate fuel for a pressure washer will differ from one model to another. But generally, the fuel should at least meet the following conditions;
- Have an 87-octane rating
- Have at most 10% ethanol
- It shouldn’t be old than 30 days
How to Fix:
If the fuel you’re using for your pressure washer doesn’t meet all of these conditions, it’s not the ideal fuel. Try and get some that does and see if that solves the problem. Of course, you’ll need to remove all the old fuel first before adding fresh fuel.
3. Faulty Spark Plug

Spark plugs are essential to any engine, be it in a pressure washer or car. The spark plugs are responsible for creating the spark that ignites the fuel and air mixture in the engine, thereby triggering combustion.
If the spark plugs are damaged or dirty, they won’t be able to create the necessary spark. That’s because, as we all know, electricity won’t flow easily through a dirty or damaged conductor. So, the engine will either stall or run on choke.
How to Fix:
To fix this problem, you’ll need to clean or replace the spark plugs. Usually, a simple cleaning with compressed air will do the trick. But if they’re too damaged, you might need to replace them altogether.
4. Leak From Air Filter
For an engine to work, there are a lot of conditions to fulfill. One of them is having the proper air-fuel mixture. The fuel has to be mixed with just the right amount of air for combustion to take place. Otherwise, the engine will stall or run on choke.
One potential reason behind an air-fuel mixture that’s not ideal could be a leak in the air filter. A leak from the air filter means inadequate air for the fuel to mix with. That will, in turn, affect the combustion happening in the engine.
How to Fix:
To solve this problem, you’ll need to check the air filter for any holes or leaks. If there are any, you can try and patch them up with duct tape or a similar material. If that doesn’t work, then you’ll need to replace the air filter altogether.
5. Clogged Fuel Line
The fuel line is responsible for transporting fuel from the tank to the carburetor. If it’s clogged, then chances are fuel won’t be able to reach the carburetor. And as we all know, an engine needs fuel to run. So, if the fuel line is clogged, the engine can only run when the choke is on.
How to Fix:
The solution to this problem is relatively simple; all you need to do is unclog the fuel line. You can do that by removing it from the pressure washer and then blowing compressed air through it. That will help remove any dirt or debris that might be clogging it. Once you’ve done that, reattach the fuel line and see if the problem is solved.
Ryobi Pressure Washer Only Runs On Choke
If your Ryobi pressure washer only runs on choke, it could indicate that your carburetor, fuel filter, air filter, or fuel cap are clogged. When either of these components is clogged, it can prevent the efficient flow of air and fuel to the engine, causing it to only run on choke.
You see, the carburetor plays an essential role in any engine. It’s responsible for mixing the air and fuel together in the right proportions for combustion. If it’s clogged, the mixture won’t be ideal, and that may cause the engine to only operate on choke mode.
The same goes for the fuel filter and air filter. A clogged fuel filter can prevent fuel from reaching the carburetor, while a clogged air filter can restrict airflow to the engine. Either way, it prevents the engine from running properly.
As for the fuel cap, it’s the part that allows air in as the fuel in the tank gets used up. That ensures smooth fuel flow to the engine by preventing the formation of a vacuum that could otherwise emanate from the fuel being drawn out of the tank.
So, if your Ryobi pressure washer only runs on choke, you’ll need to clean or replace the carburetor, fuel filter, air filter, or fuel cap. Usually, a simple cleaning should suffice. But where the damage is severe, you only need to replace the component altogether.
Honda Pressure Washer Only Runs On Choke
For Honda pressure washers that only run on choke, possible causes include inadequate fuel in the carburetor and issues with the carb, spark plug, fuel pump, and other parts playing essential roles in the engine.
One way to check if there’s adequate fuel in the carburetor is by looking at the primer bulb. If it’s hard to press or takes a long time to come back up, then the carburetor isn’t getting enough fuel.
As for the carb, it could be clogged. That’s why it’s essential to check and clean it regularly. Other parts to examine are much the same as with any other pressure washer; these include the air filter, fuel filter, and spark plug.
Fuel pump problems are another possible cause of a Honda pressure washer that only runs on choke. If the fuel pump is not working properly, it can prevent fuel from reaching the carburetor. So, if all else fails, make sure to check the fuel pump.
How Long Should You Leave The Choke On?
Usually, you won’t need to keep the choke on for more than 5 minutes. Leaving the choke on for too long can damage the engine. So, once the engine has started, take the choke off. If you can do it sooner, the better! The more it stays on, the greater the chance of damaging the engine.
As much as the choke helps start the engine at low-temperature conditions, it’s not meant to be used for long periods. It’s simply an easy but unsustainable way to get the engine going. So, once it does its work, take it off to avoid damaging the engine.
Keeping the choke on means you’re overriding the carburetor’s regular settings. That can cause the engine to get too much fuel, flooding, and fouled spark plugs. And when that happens, you can expect your engine to wear and tear significantly.
As such, just don’t fall into the temptation of keeping the choke on for an extended period. It might seem like the easy way out, but it will only cause damage in the long run. If your pressure washer can’t run outside of the help of a choke, then you’d instead not run it until you’ve fixed the problem.
Final Verdict
If your pressure washer only runs on choke, that indicates a problem with your pressure washer. It could be a sign of a clogged carburetor, fuel system problems, or something else entirely. In either case, don’t compromise by keeping the choke on for an extended period. It’s not worth it! Instead, seek to fix the problem so you can avoid costly repairs down the road.