How To Clean Fuel Pressure Regulator [7 Easy Steps]

A clean fuel pressure regulator will keep your vehicle smooth and junk-free. If you want your vehicle to run smoothly without any dirty gas pressure, make sure you’re keeping the regulator clean. 

A dirty or bad fuel pressure regulator can cause blockage/clogs. Besides, a dirty pressure regulator can cause you to spend a lot of money with time. An unclean fuel pressure regulator will not only affect vehicle performance but also might cost massive damages. 

What Is Fuel Pressure Regulator & How It Works

The fuel pressure regulator is a device in the engine that maintains the right fuel pressure in your car. The fuel pump sends as much fuel pressure as it can to ensure a steady supply of fuel.

what is fuel pressure regulator & how it works

But that high pressure isn’t always needed. That’s where the fuel pressure regulator comes in and acts as a block to reduce the pressure created by the fuel pump. That reduction in pressure creates a steady fuel pressure that the engine needs.

The fuel pressure regulator has two sides – one side gets the pressure from the fuel rail and the other side gets pressure from the inlet tract. It has a bypass valve that opens and closes as necessary to maintain the right fuel pressure even during drastic changes.

What Are The Bad Fuel Pressure Regulator Symptoms

Here are the most common symptoms of a bad fuel pressure regulator:

1. Poor Engine Performance

You’ll notice a drop in the engine performance when you have a bad fuel pressure regulator. A bad fuel pressure regulator can lower the fuel pressure and make the engine stall, hard to start, and run rough. It also causes the engine to misfire frequently and poor acceleration as well.

2. Engine Backfiring

One of the first symptoms you’ll notice when you have a faulty fuel pressure regulator is that the engine will backfire. You’ll hear a loud sound that may seem like a gunshot when it happens.

engine backfiring

It’s usually heard during acceleration as unburned gas starts to burn in the exhaust system.

3. Black Exhaust From Tailpipe

One of the strongest visual symptoms of a bad fuel pressure regulator is black smoke coming from your tailpipe. It’s an indicator that your engine is burning too much fuel and your car is running rich.

4. Check Engine Light Will Be On

A faulty regulator will trigger the engine light to come on. When it burns too much fuel, it’ll increase the carbon emissions and that causes the engine light to turn on.

5. Fuel In Vaccum Hose

The vacuum lines in the engine bay are connected to the fuel pressure regulator. When it goes bad, the fuel can end up in these vacuum lines or hoses. Detach the vacuum line and check whether there is fuel in it. If there is fuel, it’s a strong indicator of a bad fuel pressure regulator.

6. Leaking Fuel

The diaphragm in the fuel pressure regulator can be worn out with time if you use poor-quality fuel. That’ll cause the seals in it to erode and leak fuel. You’ll sense the smell of gasoline when there’s a fuel leak.

7. Black Spark Plugs

A bad fuel pressure regulator makes the engine run rich and the effects of it can be seen by inspecting the spark plugs in the combustion chamber of your car.

black spark plugs

If the tip of the spark plugs is covered with a substance that appears to be like black powder, it’s most likely caused by the fuel pressure regulator.

8. Bad Fuel Economy

You’ll be burning through more fuel when you have a faulty fuel pressure regulator as it’ll send more fuel to the engine. That’ll cause the fuel economy performance to be reduced.

9. Loud Noise From Fuel Pump

Fuel pumps are known to be loud and you most likely always hear them for a while when you turn on the engine. But if the noise is more annoying than usual and there’s a “whirring” sound coming from it, either the fuel pump itself is bad or the fuel pressure regulator is malfunctioning.

10. Engine Not Starting

An engine not starting or turning over could be the result of a bad fuel pressure regulator. Because it takes the correct ratio of air to fuel mixture to start a car and without the regulator, it won’t be possible in some cases.

engine not starting

But there are many other reasons that can keep the car from starting such as a dead battery, bad alternator, or a lack of fuel. So, check it with the other symptoms to confirm if you actually have a bad fuel pressure regulator.

How To Recognize An Unclean Fuel Pressure Regulator

A fuel pressure regulator will ensure your vehicle is getting a 100% efficient fuel supply. Have you ever wondered how your regulator requires cleansing?

Well, there are specific issues that show up bad pressure regulators & whenever a fuel pressure regulator needs cleansing. For identifying these issues, you should compare how does a fuel pressure regulator work and how your one is working. Check if your vehicle is creating such issues or not: 

unclean fuel pressure regulator
  • An unclean fuel pressure regulator will hamper your vehicle’s fuel efficiency.
  • A dirty fuel pressure regulator will create unusual noises and vibrations. However, it’s considered normal to make slight noises. But if your fuel pressure regulator is stuffed with junk, it will create more irritating noise.
  • Your vehicle motor will not serve a great start.
  • An unclean fuel pressure regulator will push weaker acceleration. This will make your vehicle consume a higher amount of fuel. As a result, you will have to spend extra bucks.
  • If you do not clean fuel regulatory pressure, it can create gas leakage. If you notice any fuel dripping, it might be a result of the filthy regulator.
  • Another symptom of unclean fuel pressure regulators is they will create filthy black smoke more than usual.
  • An unclean fuel pressure regulator can create insufficient velocity in the vehicle. 

If you notice any of these issues or symptoms, clean your pressure regulator immediately. Besides, it has been so long since you’ve cleaned the regulator, try to hold up the regular cleansing to avoid any vehicle performance hassle.

How To Clean Fuel Pressure Regulator [Step By Step Guide]

A junk fuel pressure regulator is never expected. Everyone must stay conscious with regular cleansing. However, it’s vital that you’re cleaning the fuel regulator in the right way.

Any wrong steps can make your fuel pressure regulator stuck closed. Here you’ll get the entire procedure instructions step by step. Follow the procedure here: 

Step 1:

Firstly, you have to detach the power system. For that, you can separate the battery cable entirely. Disconnecting this battery cable will balance your vehicle fuel system. You can’t avoid this step as it will create pressure to fuel squirt and influence injury.

detach the power system

But don’t forget to give it a check after detaching the battery. Try to start your vehicle and check if it’s supplying any energy or not. 

Step 2:

Next, you have to detach the gas cap in the fuel tank from your vehicle. This step will prevent providing extra pressure. 

detach the gas cap in the fuel tank

Step 3:

Now, the thing that will make you concerned is the extra pressure of the fuel injector. After releasing that, you need to find the vacuum hose and detach it from fuel lines. This step will make the further procedure easy and safe. 

Step 4:

Next, you have to detach the retaining bracket of the regulator. Generally, these brackets are sealed with screws and clips. You can use some handy tools to remove the screws easily. You can use the step with your hands too. All you have to do is use some cloth to avoid slippery fuel rails. 

Step 5:

Once you detach the regulator from the fuel rail, dispose of the O ring. If your fuel pressure regulator is dirty, the O ring can appear super filthy. 

detach the regulator from the fuel rail

Step 6:

Now, this is the ultimate time for cleansing. For cleaning the parts, you have to disconnect all the individual parts and clean them. For better cleansing, you can take a soft and tidy piece of fabric. Once you do all the cleansing, give a final check if it has got any residue left or not. 

Step 7:

Finally, you need to gather everything back and place the regulator in its own place. You can reverse the same process that you mentioned while detaching the parts of your fuel pressure regulator. 

These are the basic instructions that you need to maintain while cleaning your fuel pressure regulator. The steps are super handy and straightforward. However, if you’re extremely nervous and want some guidance, take some help from a professional. Also, you can follow the below tutorial on how to open the fuel pressure regulator and change it.

Benefits Of Cleaning A Fuel Pressure Regulator

Now that you’re aware of the problems that are caused by a bad fuel pressure regulator, you know the importance of keeping them clean. Here are the reasons why should clean the fuel pressure regulator:

1. Regulate Fuel Pressure

The main job of the fuel pressure regulator is to regulate the fuel pressure at all times. Cleaning it will do just that and make sure that you maintain steady pressure throughout your journey.

2. Good Engine Performance

Your engine will run as smooth as butter when you have a clean fuel pressure regulator as long as there are no other issues in your car. It’ll start well without any issues and you’ll also get great fuel economy because of it.

Tips For Cleaning Fuel Pressure Regulators

Here you’ll get some tips and suggestions that can make the entire fuel pressure regulator cleansing handy. With all these tips, you can make the process super fun. Follow the tips here:

  • Before you start with the fuel pressure regulator, check for leakage. For that, you can turn your vehicle’s ignition system on for a few seconds. Then turn off the system for around ten seconds. Then, again turn the ignition system on. This tape will make it visible if there is any leakage or not. 
  • If you have any white piece of napkin, grab that to clean your fuel pressure regulator. It will make the cleanliness visible. 

How To Test Fuel Pressure Regulator

You already know the symptoms of a bad fuel pressure regulator. You’ll see your engine misfiring frequently, backfiring, fouled spark plugs, and black smoke coming from the tailpipe when there are issues with your fuel pressure regulator.

But if you’re still having trouble diagnosing a faulty fuel pressure regulator, you need to know the correct fuel pressure for your vehicle by taking a look at your owner’s manual or looking it up online.

how to test fuel pressure regulator

The next step is to use a fuel pressure gauge and see if you’re getting the correct pressure or not. If the fuel pressure is too high, your fuel pressure regulator is the main culprit behind it and you need to clean or replace it depending on the severity of its condition.

How To Unstick A Fuel Pressure Regulator?

If your fuel pressure regulator is stuck and you want to unstick it, turn off the engine and wait for it to cool down first. Then, spray some WD40 or other lubricant on it to unstick it.

how to unstick a fuel pressure regulator

If that doesn’t do the trick, you need to pull it out and give it a thorough cleaning. Follow these steps to remove the fuel pressure regulator from your vehicle:

  • Make sure the engine is cool and disconnect the battery.
  • Disconnect the vacuum line connected to the regulator.
  • Unscrew the bolts that keep the regulator in its place.
  • Put a paper towel around the regulator as it’ll be leaking fuel when you take it out.
  • Gently pull out the fuel pressure regulator.


Can a fuel pressure regulator get clogged?

Yes, if you don’t clean the fuel pressure regulator properly, in the long run, it can get clogged. This clogging will block and hamper the fuel pressure regulator. 

How often should you change the fuel pressure regulator?

If you take care of your fuel pressure regulator, it can go over five years. After this period, you need to change the fuel pressure regulator.


If you want to keep up the efficient vehicle performance, make sure you’re cleaning the fuel pressure regulator. It can increase your expenses as well as decrease your vehicle efficiency.

This article has mentioned how to clean fuel pressure regulator with tips and suggestions. Try to follow the mentioned instructions to ensure proper fuel consumption.

About John M

John contributed as a technical head at an automobile company just 2 years after his post-graduation in Automobile Engineering. He loves to lead a free life, so he left his job & started blogging. Now, he does research on every automotive problem, part & product and seeks a better solution & best products & shares his findings with his readers to help them as well as to minimize their struggle.

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