You’ve most likely already read about the well-known EGR valve, the anti-pollution valve. It is not generally appreciated by motorists because it has a tendency to cause more concerns than anything else… Indeed, depending on the use you are going to make of your vehicle, it can become congested and cause you a lot of complications. If this is the situation, you are most likely concerned about how to clean the EGR valve of your Mazda CX 7 ? Don’t get worried, we’ve made this article to help you with this process. To achieve this, we will initially look at the goal of the EGR valve, then what are the failures that the EGR valve of your Mazda CX 7 can provoke and at last the part that will most likely concern you the most, how to clean the EGR valve Mazda CX 7?


How to Clean your Mazda CX 7 EGR Valve: Role and Operation

Role of the EGR valve

The EGR valve of your car has been added to diesel engines mainly to reduce pollution released by vehicles and to fulfill EURO measures on Mazda CX 7 . It will as a consequence influence the quality of exhaust gas output and reduce toxic particles, mainly Nitrogen Oxide.

Operation of the EGR valve

Before we discover how to clean the EGR valve on your Mazda CX 7 , we will examine how it functions. As seen before, its objective is to clean the exhaust gases, so it will be positioned at the engine outlet, thanks to a valve, it will be able to return the unburned exhaust gases to the engine for a second burn which will reduce all unburned toxic particles. It will operate mainly at low speed because at high speed the combustion is enough to burn all these gases.

How to clean your Mazda CX 7 EGR valve: Identifying faults

The EGR valve, although very beneficial to limit the pollution emissions of your Mazda CX 7 , will sadly tend to clog up because of soot/gas deposits that will build up in its system, which will inevitably risk obstructing the operation of the valve, until completely blocking the engine, here are the signs of illness that a faulty EGR valve on your Mazda CX 7 can trigger:

  • Motor light on
  • Performance loss
  • Technical inspection rejected
  • Black gases
  • Car that grazes at low speed
  • Low RPM settings

How to clean your Mazda CX 7 EGR valve: In practice

And now we’ll commence the part you are most enthusiastic about, how to clean the EGR valve of your car. Here are the two approaches that you can use.

Do it on your own

How to clean your Mazda CX 7 EGR valve system: Without dismantle

Nevertheless this methodology is less effective, it is however possible to consider a “rough” cleaning of your EGR valve, in reality, you will only need to use fuel additives, similar to the products used to clean the injection. These specific products must be injected into the running engine, at the right operating temperature, diluted in about 20 litres of fuel and run the engine for 3 or 4 minutes in high rev to clean the EGR valve of your Mazda CX 7.

How to clean your car EGR valve: With disassembly

Here is the strongest methodology, which will require enough access to the EGR valve to do the operation on your own. If so, the process is fairly easy. You will need to disconnect the electromagnet from the EGR valve, remove the few screws that hold it in place, and remove it. Once these guidelines are accomplished, now comes the time for cleaning. To accomplish this, you will need to use a product such as solvent, petrol, oven cleaning product, which you will leave to act for ten minutes, then scrape off the rest using a scraper, finish cleaning with wire brush. If you want to go further, you can also clean the two canal on which it is connected which may be scorched, for this, use a scraper and a vacuum cleaner to avoid dropping deposits in the conduits. You will only have to reassemble it and you will have finished cleaning the EGR valve of your Mazda CX 7.

Have it done by a professional

If, your EGR valve is not accessible because of the series or the engine of your car and if removing it would cause too many complications (removing too many auto parts that hinder access for example), how to clean the EGR valve of your Mazda CX 7? In cases like this, it would be better rather than launching yourself into an overly complex process, you turn to an auto mechanic. He will be able to carry out the job more cleanly and will be able, if required, to change the valve if it is dead. The cost of cleaning depending on the difficulty of access is between 70 and 300 €.

Remove the EGR valve of your Mazda CX 7

Finally, some people make a more radical decision to limit the risk of a failed valve. Instead of cleaning the EGR valve of their Mazda CX 7, they just prefer to block it in the closed position. This modification will have the result of greatly increasing the pollution released by the vehicle, of no longer complying with pollution requirements, of having an engine warning light all day on and ultimately risk fouling the engine. We highly advise against making this choice. If you have other questions or want to learn more about your car, don’t be reluctant to take a look at our dedicated page.

To get more tips on the Mazda CX 7, take a look at the Mazda CX 7 category.