Quality full-range EGR servicing - restoring the lost efficiency or disabling the exhaust gas recirculation valve and the EGR cooler. Available for passenger cars, trucks and industrial vehicles. Problem solving by field experts.



Find out the exact cause of system failure and return it to working condition


Cleaning of a clogged EGR valve and restoring the operability.


Full-range EGR servicing - including mechanically blocking the supply of exhaust gases (or complete removal of the EGR valve) and ECU software reprogramming. 


Fix the problem of a leaking EGR cooler or remove it completely and have specially made plugs installed instead.
Below you will find a detailed description of this system, causes of its failure, and problem solving options that will help to determine the best repair procedure for you. No time to read? Just call or write to us, and we will help you choose the best option.


EGR valve functions

All modern diesel cars have an exhaust gas recirculation valve, commonly referred to as EGR or AGR. This is a part of both the intake and the exhaust systems that is designed to reduce the combustion temperature of the fuel-to-air mixture in the cylinder (by reducing the amount of oxygen) in order to reduce the amount of NOx (nitric oxide) in exhaust gases and to improve environmental characteristics. It also performs secondary burning of the exhaust gases in the engine (hence recirculation) that in theory should be better for the environment.
It functions quite simply - this valve deflects part of the exhaust gases from the exhaust manifold to the intake. There exhaust gasses mix with fresh air and re-enter the engine.


EGR valve problems

Despite the apparent simplicity, the EGR valve is a rather complicated and sensitive mechanism. It works in a very narrow range of RPMs and loads. Faulty operation of EGR valve often leads to significant problems. Signs of a faulty valve are:

  • "Check Engine" lights up on the dashboard (and also coil icon in VAG-group cars).
  • Car sputters, smoke appears from exhaust, engine stalls. 
  • Power drops sharply or car jerks constantly when accelerating.
  • Sputtering with a cold engine that disappears after warm-up or vice versa.
  • Dirt build-up in the engine intake system.
  • Dramatic increase of fuel consumption.

Why EGR fails? It's simple - in 90% of cases it becomes clogged up with exhaust tar and sediment. In other words - it fails due to the build-up of impurities that the EGR itself creates inside the engine. 10% cases of failure are attributed to wear or electrical problems. And where are these impurities coming from? Part of exhaust gases re-enter the inlet manifold after being a cooled in the heat exchanger. During the cooling, a thick layer of tar deposits starts to build-up. It is the EGR that creates all these impurities that are observable in the intake manifold. This causes a significant drop in the power output and the failure of swirl flaps in the intake manifold as well. Majority of EGR valves also have their own radiator (heat exchanger) to cool down the incoming exhaust gases. Over time this radiator starts to leak and causes constant leaking of coolant. As you can see - this valve causes a significant amount of headaches.



Faulty valve Replacement for new one

The easiest option is simply to replace the faulty EGR with a new one. Advantage: system works again. Cons: the recirculated exhaust gasses will still get into the engine and clog up the intake manifold - same as before. Problems will reoccur in the future. Price of a new EGR may exceed 1000 euros on some models. Replacement/installation service can cost a considerable amount in itself depending on the engine configuration and how accessible the valve is in engine bay. Some cars feature 2 EGR valves - both of them need to be replaced together.

EGR valve mechanical cleaning

Another method is to do a deep cleaning by using special chemical agents - this restores the valve to its full potential only if the malfunction was caused by clogging up. The cost for this procedure varies depending on the design of the valve and the complexity of installation, and the procedure is performed by disassembling the valve completely. Advantage - the valve operability is completely restored. Disadvantage - problem reoccurs in the future, further ingression of impurities into the engine. 

EGR valve Disabling or removing

This is the most effective method - it solves problems once and for all. The valve is mechanically blocked in the closed position (if necessary) and the engine control unit software is modified to operate without this system. Advantages: problem is solved once and for all; fresh air enters the engine; sediment no longer deposits in the intake manifold and on valves and the cylinder-piston group; slight increase in power due to combustion of a clean fuel-to-air mixture that does not contain any exhaust gases in it. Cons: increased NOx emissions. In some cases, the DPF unit also needs to be removed. Professionally performed disabling or removal will not cause any black exhaust plumes, MOT inspection failures, etc. - these problems are a direct indicator that poor-quality service was provided - we'll later discuss this more in detail. Another advantage of this procedure - problems with EGR cooler will be solved permanently by removing it completely.

Example of a complete EGR and EGR cooler removal

EGR valve deactivation: ecology, black exhaust smoke, MOT test

Some car owners face problems after EGR removal - the car starts to smoke heavily, errors light up, and difficulties passing MOT inspection are experienced. The root cause of problem is not the fact that the EGR is removed - it is the direct representation of quality of services provided by incompetent amateurs in cheapest service centres out there. By entrusting the EGR removal to experts you are protected from such "perks". Guaranteed. There is a huge difference between tuning provided by professionals using proven and certified solutions and non-professionals with “disablers” that sometimes do not understand at all what must be done and how. Redoing work after such a "service" is sometimes several times more expensive than doing everything properly initially.  
Ecology: contrary to popular belief the EGR valve shutoff has virtually no effect on NOx increase in the exhaust. Firstly, quantity of NOx depends directly on the quality of fuel used. In other words - when using sub-par quality fuel of unknown origin, a car with an operating EGR valve will be less environmentally friendly than a car that has EGR removed and runs on quality fuel. Second, the EGR valve is not in an open position all of the time! It functions in a narrow range of RPMs (usually up to 700 - 2000 RPMs). Rest of the time is spent in a closed, so it does not reduce NOx concentration in emissions when in a closed position. Third, the EGR valve opens only when the engine reaches a temperature of 50 - 60 degrees Celsius. Up to this temperature the valve is closed at any RPMs. So - if the car is used for short urban commute, then the valve has no chances to open, therefore NOx content in emissions is not reduced during 90% of the engine runtime. Only those drivers who are stuck in the traffic for long periods of time and are using fuel of excellent quality, and do not exceed revs above 2000 make their "contribution" to the environment.
MOT: it's impossible that your car won't pass MOT test when the EGR valve is shut off - when the MOT inspector steps on the accelerator pedal and engine revs exceed 1800 RPMs, the EGR valve is in a completely closed position anyway - even in cars with a fully functioning EGR valve. So your modified car will produce the same figures as a car with an operational EGR valve.
Black smoke, sputtering, uneven operation, etc.: after the EGR removal is solely an indicator of competence. Such problems do not arise when the EGR removal operation is performed correctly.



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