5 Bad EGR Valve Symptoms

5 Bad EGR Valve Symptoms

Do you know any EGR Valve Symptoms? Modern vehicles now have more sensors, electrical parts, and emission components than ever before. But while they can be a little frustrating when they aren’t working as they should, they really make a big difference.

So, instead of cursing the newer components, let’s take a look at what the EGR valve does and how you can diagnose a faulty one. We’ll give you everything you need to know to get your vehicle back on the road.

What Does an EGR Valve Do?

Before you can diagnose a faulty EGR valve, it’s best to know what an EGR valve is and what it does.

Many older vehicles don’t have EGR valves, but as governments and vehicle manufacturers put more of an emphasis on emission standards, EGR valves became commonplace. Now almost all new vehicles come with EGR valves.

The way an EGR valve works is simple. They capture burnt fuel vapors in the exhaust and force them back into the engine to burn again. Not only does this help reduce the amount of harmful NOx emissions coming out of the tailpipe, but it also improves fuel economy by reusing fuel vapors.

Top 5 Bad EGR Valve Symptoms

While the first noticeable symptom of a bad EGR valve will likely be a check engine light, you’ll start to notice more and more symptoms arise over time. If you know what you’re looking for, it’s easy to spot an EGR valve on the fritz, and we’ll walk you through everything you need to know here.

1. Check Engine Light

Vehicle manufacturers fill modern automobiles to the brim with sensors. They measure everything imaginable from air intake to the effectiveness of the catalytic converter. So, it’s no surprise that there’s a sensor monitoring the performance of the EGR valve.

And when something doesn’t add up a check engine light will illuminate. The most common check engine light associated with a faulty EGR valve is a code P0401, although a few different codes could signify a problem with the EGR valve.

2. Failed Emissions Test

One of the primary purposes of the EGR valve is to reduce emissions – so it makes sense if you have a bad EGR valve, you’ll fail an emissions test. By failing to recirculate the emissions properly the amount of NOx escaping the tailpipe will increase.

While this is technically only a problem if you live somewhere with emissions tests, if you’re trying to do what’s best for the environment, you should replace your EGR valve as soon as possible too.

3. Reduced Fuel Efficiency

Reduced Fuel Efficiency

While the primary purpose of the EGR valve is to reduce the number of emissions that your vehicle gives off, another perk you get as a driver is improved fuel efficiency. This makes sense because while there might not be as much energy stored in burnt fuel vapors as fresh fuel, there is still some there.

Your vehicle gets to use this energy, reducing the amount of fresh fuel you need to dump into the engine. But now that you’re not reusing the burnt vapors, you need to depress the pedal further to achieve the same results, which translates to more fuel consumption.

4. Reduced Engine Power

If there’s not enough fuel in the combustion chamber, then your vehicle won’t be able to get the most out of each rotation of the engine. This means you’ll need to depress the gas pedal further to achieve the same results, and this will reduce your top-end power.

Not only that, but since you’re used to only needing to depress the pedal a specific distance to achieve your desired results, you’ll likely find that you’re not accelerating as quickly as you would’ve if your EGR were operating correctly.

5. Rough Engine Idle

While you can make up for less fuel by depressing the pedal further, one time you’re not depressing the pedal is when you’re idling. At this time, your engine isn’t getting enough fuel to keep everything running smoothly since it’s expecting the EGR valve to supply a little.

What this translates to is a rough idle. It shouldn’t be severe enough to shut off your engine, but if you know what a healthy idle sounds like, you’ll be able to notice a difference.

Cleaning an EGR Valve

Cleaning an EGR Valve

While vehicle and part manufacturers will tell you that you’re not supposed to clean an EGR valve, it’s a fairly common trick to extend the life of the component. In fact, we recommend trying to clean your EGR valve before ever ordering a replacement.

It’s 100 percent safe, easy to do, and can extend the EGR valve’s life by thousands of miles. All you need to do to clean the EGR valve is remove the valve and spray it down with carb cleaner.

Carb cleaners like the Gumout Carb and Choke Cleaner are incredibly cheap and get the job done. From there, use a soft wire brush and dull scraper to clean off any carbon deposits!

Gumout 800002231 Carb and Choke Cleaner, 14 oz.
  • Helps overcome hard starting, rough idling, stalling, and high exhaust emissions
  • Quickly removes deposits from the inside and outside of the carburetor to improve engine performance and fuel economy
  • Cleans gum, varnish, and dirt from clogged carburetors and choke valves
  • Effectively cleans unpainted metal parts and is quick drying

EGR Valve Replacement Cost

If you’re unable to clear the code after cleaning an EGR valve, you’ll need to fork out a little more cash. Because while the EGR valve might be a small component, that doesn’t mean that replacing it is will be cheap. In fact, if you take your vehicle to a repair shop, you can expect to spend anywhere from $350 to $400. However, this cost will vary depending on what you drive and where you take it for repairs.

The bad news is that even if you’re looking to replace the valve yourself, you’re still going to spend close to $300. That’s because the majority of the EGR valve cost is parts. But there is a little good news. When it comes to automotive repairs, an EGR valve replacement is relatively easy.

You can usually find the valve towards the top of the engine, so with even a little mechanical know-how, you should be able to figure out the job and be able to do it yourself.

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