Exhaust Gas Recirculation


Schematic diagram of EGR System

Exhaust Gas Recirculation

The Exhaust Gas Recirculation or EGR system is one part of several vehicle emission control systems. It reduces the amount of the nitrogen oxides (NOx) in exhaust gases. Nitrogen oxides are normally formed in the process of combustion and their formation increases dramatically at higher combustion temperatures (above 1600 °C or 2912 °F).

Higher combustion temperatures are also harmful to the engine. One of the effects caused by high combustion temperatures is a pre-ignition or detonation (pinging), when the air/fuel mixture ignites in the cylinders not from the spark, but from excessive heat. Because it happens at the wrong time before the spark, the detonation adds additional strain on engine components.

Prolonged detonation can damage valves, pistons and other components. A turbocharger also fails sooner when exposed to excessive heat.

The EGR system reduces combustion temperatures by diverting a small portion of exhaust gases back into the intake manifold. Exhaust gases are no longer combustible so diluting the intake air with exhaust gases makes the air/fuel charge less combustible. The engine management system opens or closes the EGR valve to control the flow within the EGR system. The EGR valve connects the exhaust manifold to the intake manifold. The EGR valve is normally closed. There is no EGR flow when the engine is cold, at idle, or during hard acceleration. EGR flow is at its peak during steady cruising under moderate load.

The engine computer (PCM) opens or closes the EGR valve to control the flow within the EGR system. The EGR valve connects the exhaust manifold to the intake manifold. The EGR valve is normally closed. There is no EGR flow when the engine is cold, at idle, or during hard acceleration. The EGR flow is at its peak during steady cruising under moderate load.

FAQ regarding Exhaust Gas Recirculation(EGR)

As an owner/driver of a Diesel powered vehicle you need to clean the EGR cooler and valve regularly as this will save you money in operating costs, reduce engine wear and prevent costly downtime in the long run.

Maintenance schedules or cleaning cycles vary according to the type of vehicle and how your vehicle is being used.

To keep your EGR’s optimal operating performance we suggest a clean at least every 12 months. Shorter timeframes may be needed if your vehicle is exposed to:

  • Short trips/city driving (Clean every 30000km)
  • Long trips/freeway driving (Clean every 50000km)
  • If your vehicle has had a failure with fuel injectors, turbo, head gasket, excess oil consumption

For vehicles that operate on the highway at least once a week or more for periods of at least 30 minutes at a time, we recommend a full EGR service and clean every 50 000km providing the below issues have not affected the operation of the EGR.

  • Poor fuel consumption
  • Noticeable decline in performance
  • Rough idle and poor acceleration if the EGR valve is stuck open
  • the smell of fuel if the EGR valve is stuck closed
  • Engine light comes on
  • If your vehicle has had a failure with fuel injectors, turbo, head gasket
  • Engine knocking (untimed detonation) caused by a blocked EGR will eventually destroy the inner components of your engine, requiring overhaul or replacement. Imagine all that hassle over a small component that you can easily clean!

Exhaust Clean Australia guarantees the fastest turnaround times in the market due to our revolutionary Flash Clean technology. This patented Italian made machine is the best of the best, guaranteeing the fastest clean and the very best results or your money back.

We can pick-up from your workshop and deliver your EGR back in as little as 3 hours. We offer a range of services, including:

  • Priority Service (next in line)
  • Same day service
  • Standby budget service

Exhaust Clean Australia offer warranty on all our workmanship where the vehicle is operated according to manufacturer’s specification.

Pricing structure here:

From as little as $ ? . Compare that the cost of a replacement EGR cooler and valve that could set you back anywhere from $200-1000 for cars, and in excess of $1500 for large trucks and machinery. Cleaning your EGR is a very cheap cost alternative for your car, truck or machine.

Pricing structure here:

  • Diesel particulate filters – from $450 + gst
  • Cat Convertors – from $340 + gst
  • Diesel oxidising catalysts – from $340 + gst
  • Selective catalyst reductors – from $390 + gst
  • Intercoolers – from $110 + gst
  • Exhaust gas recirculation – from $100 + gst

There are many different concoctions on the market that claim to be able to clean EGR’s. They are extremely ineffective and a waste of your hard earned money. Exhaust Clean Australia using the patented revolutionary technology we possess can clean your EGR valve and cooler and make it like new again!

To help prevent your EGR from being contaminated ensure that the vehicle’s service schedule is adhered to and correct engine oil is used. Find an independent mechanic that is familiar with your make and model of vehicle and is experienced in servicing modern diesels. This will ensure that they have a thorough knowledge of your vehicle and will know all the tips and tricks in fault finding any problems. Cleaning your EGR on a regular occurrence will dramatically reduce the risk of it becoming blocked!

EGR systems are very technical and some mechanics may not fully understand their complex operation, and in our experience that also includes some dealerships. Some workshops may use the “keep replacing parts” method hoping it’ll solve the fault, but inevitably your bank balance will cop a hiding! Try to find a diesel specialist workshop that frequently deal with EGR systems and understand how they work. They’ll be able to pinpoint the cause of the fault and only replace or repair the parts that are necessary. More often than not an EGR system just needs a thorough clean to return to a perfect working order and that’s why Exhaust Clean Australia is here to assist you!

Exhaust Clean Australia can provide a removal and refit service of your EGR at our workshop for all vehicles sizes. We can also provide a list of recommended mechanics in your area that can perform the removal and fitting service for you, while ensuring that your EGR is still being cleaned by the best in the business.

No, it’s illegal to remove or delete your EGR. Your vehicle has been designed by the manufacturer to operate with an EGR system. It is illegal and will also void the manufacturer’s warranty on your vehicle and Australian consumer law protections. Removal or deletion of your EGR will also impact your vehicle’s insurance policy.

EGR’s are fitted to enable the vehicle to comply with the Australian Design Rules (ADR) emission requirement levels.

The relevant ADR for light vehicles is ADR79/03

The relevant ADR for heavy vehicles is ADR80/01

It is illegal to operate a vehicle that does not meet the ADR requirements so removing or deleting an EGR will result in non-compliance with all relevant emissions ADR’s.

In addition to commonwealth legislation, each state and territory also have additional legislation that require EGR’s to be fitted and operated in accordance with manufacturer requirements.

Don’t be fooled by dodgy operators that claim to electronically delete the operation of your EGR without detection. Authorities are now cracking down on engine tuning shops and vehicle owners who employ this practice, using sophisticated tools to identify vehicles suspected of having no EGR or deleted EGR’s. Stiff prison sentences are now being applied for this practice, with numerous prison sentences already handed down.

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