car remapping

Vehicle Maintenance: 3 Signs You’ve Got a Bad EGR Valve

After a few years of use, the average vehicle begins to show certain signs that it’s not running at 100 per cent. Of course, this can be an alarming sign for any driver because of how foreign the feeling of things going wrong can be. 

Whether you’re driving a sedan, SUV, minivan, or sports car, you may be able to immediately tell that something’s up with it. Certain symptoms may have you worrying, from shudders during traffic idling to delays in shifting and slipping clutches.

If a car begins to show signs of poor performance and decreased mileage, it can be very worrisome because of how difficult they are to fix. There’s very little that you can point to apart from one increasingly common issue: a faulty EGR valve. 

What Is an EGR?

Exhaust gas recirculation (EGR) valves seek to reduce the overall amount of NOx pollutant (nitrogen) emitted by a vehicle. The way this happens is that the valve recirculates emissions back into an engine’s combustion chambers rather than sending them outwards.

In terms of classifications, these valves come in two different forms found in vehicles all over the United Kingdom: 

  1. Valves that are operated by vacuums, and;
  2. Valves that are operated by the engine control unit (ECU) or engine control module (ECM)

What Are the Signs of a Bad Valve?

EGR valves minimise the chances of an engine becoming a major pollutant on the roads due to the way it’s constructed and engineered. However, the problem with these components is that they tend to fail out of nowhere and end up compromising a vehicle’s function. 

To help ensure that you don’t end up facing issues on the road because of a simple valve malfunction, here’s a quick rundown of the warning signs you should watch out for: 

1. Lower Fuel Economy

Whenever a car begins to experience issues with its EGR valves, it’s most likely going to emerge in the form of a lower fuel economy. This ends up happening is because of a valve getting stuck open, which leads to lower temperatures inside combustion chambers and more petrol being consumed. 

2. Rough Engine Idling

Another distinctive sign of a poorly functioning EGR valve is a rough idling sensation whenever a car is cruising or in neutral. This particular issue occurs when the valve is stuck in an open position, which eventually leads to too little or too much exhaust gas being sucked into a combustion chamber.

3. Stalling While Idle

If your car begins to stall while idling, then chances are that you’re dealing with a faulty valve. Again, this occurs when a valve is stuck in an open position, which muddles the air-fuel mixture in the injectors, resulting in sudden ignition misfiring. 

What Should You Do?

Whenever your car starts experiencing symptoms related to faulty valves, the best thing to do is to bring it straight to your local garage for a full check-up. If you want a complete solution, get an ECU tuning expert like Carlton Tuning take care of your car with a remap or EGR valve delete or replacement! 


Dealing with a faulty EGR valve can be confusing and hectic. By being mindful of this guide, you can act as quickly as possible to protect your car and keep it in tip-top shape! 

Taking your car’s performance to the next level has never been easier, thanks to Carlton Tuning’s ECU remap service in Barnsley, South Yorkshire. If you want to leave your beloved ride with a team of experts that can professionally handle your needs, look no further because we’ve got you covered, so schedule an appointment with us today!

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