Not only does the EGR (exhaust gas recirculation) system in your vehicle cut down on emissions, but it also helps to make your engine run more efficiently. However, in order for this to be true, every single component in the system has to be in top working order. A lot can go wrong with the system, especially since the parts are exposed to such extremely high temperatures. Manufacturers state that the majority of the parts are meant to last the lifetime of your vehicle, but this isn’t always the case.
The EGR vacuum modulator plays its own role in the EGR system, and just like all the other components and parts this part must be kept in good working order. The way this part works is that when your engine vacuum is idling, the EGR vacuum modulator closes. It is essentially a diaphragm. Once the vacuum increases, that diaphragm opens up. Should this part become broken, stuck, or even leak, then a variety of things can start to go wrong.
While there is no set amount of miles that it is meant to last, the EGR vacuum modulator does feature a filter so it will need replacing at some point. Here are some signs to watch for that could mean it’s time to replace the EGR vacuum modulator.
The engine seems to idle rough, unlike how it used to be. This could be because the EGR vacuum modulator is broken, or maybe it's leaking, or blocked. Either way YourMechanic can take a look and determine if it has reached the end of its lifespan.
There is a good chance your Check Engine light will come on. As soon as this light comes on, it's important to have it checked out by the professionals so they can read the computer codes.
Another sign is a knocking sound coming from the engine when you idle. Again this could signal the end of the road for your EGR vacuum modulator.
The EGR vacuum modulator is one of many parts involved in the EGR system of your vehicle. Without it working properly your engine will suffer. While there is no set amount of miles it is meant to last, at some point it will need replacing. If you’re experiencing any of the above mentioned symptoms and suspect your EGR vacuum modulator is in need of replacement, get a diagnostic or book an EGR vacuum modulator replacement service with a certified mechanic.
This article originally appeared on YourMechanic.com as How Long Does an EGR Vacuum Modulator Last? and was authored by Valerie Johnston.