Can a Bad EGR Valve Cause Overheating? (Yes or No)

Can a Bad EGR Valve Cause Overheating

Are you on the verge of losing your thoughts to have fulfilled all righteousness in caring for your car? Do you feel you have only your schedule to worry about now? Do you think all is set for your long adventurous journey? Check your EGR Valve!

An average automobile of any brand is fascinating. Interesting in that you have a whole lot to pay attention to and be careful in handling. The smallest of automobiles can be so demanding. While committing time and money to your car, please think about your EGR Valve too! Do pay attention to its swift beckon.

Yes! A bad EGR Valve can cause overheating. A faulty EGR Valve results in increased emission. This, in turn, breeds overheating which can cause other serious damages to your car.

Overheating is thus proof that something in the automobile is defective -as there is a level of appropriate heat. If heat is within appropriation, the word ‘over’ finds no prefix to ‘heating.’

Do note that, where a particular component is faulty, this fault either causes such part to malfunction or not function at all.

What is EGR Valve?

EGR Valve, otherwise known as Exhaust Gas Recirculation Valve, recirculates a portion of an engine’s exhaust gas straight into the engine cylinders. EGR Valve controls exhaust gas flow in recirculation, dependent on engine load.

An EGR System could be Diesel high-pressure EGR Valves, Diesel low-pressure EGR Valves, Gasoline EGR Valves, and Vacuum operated EGR Valves, Digital EGR Valves.

Functions of EGR Valve?

External Gas Recirculation Valve in the real sense of its function,  is effective largely in:

1. Lowering Combustion Chamber Temperature

The Combustion Chamber is where the mixing of fuel-gasoline and air is ignited.  While EGR performs its role, in effect, the temperature build-up is lowered. The EGR directly reduces temperature, improving fuel economy.

2. Pollution Control

As the EGR re channels a portion of the exhaust gas back into the engine cylinders, pollution to lives and properties is curtailed.

The emitted gas, which passes for poisonous if allowed into human nostrils, is used up before escaping into the atmosphere of nature containing plant, animal, and human existence.

Can a Bad EGR Valve Cause Overheating?

Yes. A bad EGR Valve can cause Overheating. The Exhaust Gas Recirculation -EGR system’s essence is to mitigate NOx -Nitrogen Oxide emissions that constitute air pollution to the outside world, so if it’s bad, it can cause overheating.

Mainly, the EGR system is used in Diesel engines. In these engines, NOx formation is the main problem based on the lean mixture and the high temperature.

Overheating is one of the first symptoms of a bad EGR Valve. The EGR restricts airflow through the cooler, affording the engine excess heat, which culminates in overheating. Heat-through-the-cooler restriction is because of carbon built up in it.

Don’t get it twisted, the EGR valve is not the same thing as the PCV Valve. They are both different and perform different yet important functions to your vehicle.

Signs Your Car is Overheating

Overheating is not to be taken too lightly. Here are some signs to intimate you:

1. Acceleration Problem

Undue dullness may be the response of an overheated engine. Once you take cognizance of strange feedback like inability to speed up or a lack of morale, you know enough to rescue your engine fast!

2. Irregular Smell

Overheated engine oil gives a ‘hot’ odor. At this time, there may be only a shadow to its ability to lubricate, and it is not the best for your car.

Do watch out! A sweet smell inside your vehicle also could be the hint you need to know that coolant leaks in the car. Coolants have a sweet-smelling property and can be extremely harsh on wildlife and the environment.

3. Steam

It could be mistaken for smoke, but it is vapor. Once it puffs out beneath the hood, it is a message -check that engine! Alongside the cooling system, note that the hood shields your engine and radiator.

The cooling system pushes coolant, otherwise known as antifreeze, through a lineup of pipes to keep your engine from overheating. As overheating is a sign of bad EGR, Steam is a sign that your coolant may be leaking.

The coolant may be so hot to be evaporating already. To know the quantity of coolant your engine is losing, and quickly so, check the quantity of steam. By a lot of steam, your engine is losing so much coolant, and this is is is is is quicker than your guess.

A large puddle under the car’s hood is another sign that coolant leaks. Coolant can boil over from an overheated engine and leak, greasing the ground. A crack or damage to other components can arise from an engine running on excess heat, causing the coolant to spill out.

With this as the case, your coolant is void of the ability to effectively run on the engine and thus can not continue working correctly. This challenge must be isolated and repaired adequately. Steps to replace the missing coolant and other damaged components must not be delayed.

4. Temperature Light/ Guage


In the instrument cluster of your car, there lies a temperature gauge. Be watchful enough to find the metering pin on your gauge resting on the “H” or see the temperature light come on. Your car needs serious help already!

How Can You Tell if EGR Valve is Bad?

A well-able EGR primarily rather efficiently should save the engine from overheating.

Once an EGR Valve cannot deliver effectively and without stress, this responsibility of its office and making it most likely is bad. You will start seeing some if not all of the signs explained above. Ensure to fix it to avoid it damaging other car components.

Disadvantages of Having a Bad EGR Valve

A bad EGR Valve causes strains in the operation of the EGR system. These strains inform performance issues like;

1. Power Reduction

The more an engine is exposed to overheating from a fault with the EGR, the more its power for efficiency and longevity reduces.

2. Increased Emissions

Rather than channel exhaust gas into recirculation, a fault with the EGR restricts and accumulates the gas in the engine.

3. A Decline in Fuel Efficiency

A functional EGR reduces temperature, thus helping fuel economy. On the other hand, a faulty EGR is disadvantageous. More fuel is consumed since the engine is subjected to more labor and pressure.

4. Impaired Acceleration

Accuracy in speed and response cannot characterize an engine that is not in good health. To the extent of ill health, every engine operates as a shadow of itself.

What to Do When EGR Valve is Bad

Please fix it. Yes! Fix it.

To forestall dangers that accompany a bad Valve, or the heavy spending that may be unavoidable based on possible damage done to some other parts, you should fix it.

It would be of no lesser pain than it would be, losing an asset if the entire knocks out eventually.


Exhaust Gas Recirculation System portrays a deep sense of mechanical intelligence on whoever invented it. The safety of drivers and non-drivers has been furnished by the advancing improvement brought to the subject by mechanical breeds professionals in this field.

Hence! No automobile driver should drive around town with a bad EGR. Likewise, no automobile user should risk ignorance or insufficient maintenance strength. A bad EGR can cause beyond Overheating.