EGR Solution and Problems
A widely adopted route to reduce NOx emissions is Exhaust Gas Recirculation (EGR). This involves recirculating a controllable proportion of the engine’s exhaust back into the intake air. A valve is usually used to control the flow of gas, and the valve may be closed completely if required.
The substitution of burnt gas (which takes no further part in combustion) for oxygen rich air reduces the proportion of the cylinder contents available for combustion. This causes a correspondingly lower heat release and peak cylinder temperature, and reduces the formation of NOx. The presence of an inert gas in the cylinder further limits the peak temperature (more than throttling alone in a spark ignition engine).
The gas to be recirculated may also be passed through an EGR cooler, which is usually of the air/water type. This reduces the temperature of the gas, which reduces the cylinder charge temperature when EGR is employed. This has two benefits- the reduction of charge temperature results in lower peak temperature, and the greater density of cooled EGR gas allows a higher proportion of EGR to be used. On a diesel engine the recirculated fraction may be as high as 50% under some operating conditions.
Here at Quantum Tuning have a very advanced solution for EGR. The valves can become clogged with carbon deposits, causing them to fail or stick, thereby causing error codes and the vehicle not to run correctly. Our software solution to disable the EGR valve is a simple and effective method of improving the efficiency of your engine.
How EGR Works?
The EGR theory works by sending a small part of inactive gas exhaust back into a vehicle’s cylinders, hence eject negligible toxins into the environment. This reduces the heat of combustion yet the same amount of pressure is still applied to this piston while reducing the amount of excess oxygen prior to combustion. A few studies conducted on diesel engines demonstrate that the portion of nitrous oxide gas emissions is definitely reduced through the use of EGR, however concentrations of smoke density can actually increase. Thus there seem to be pluses and minuses depending on what’s important to you in your specific vehicle
Usually, an engine recirculates exhaust gas by piping it from the exhaust manifold to the inlet manifold. This design is called external EGR. A control valve (EGR Valve) within the circuit regulates and times the gas flow. Some engines incorporate a camshaft with relatively large overlap during which both the intake valve and the exhaust valve are open, thus trapping exhaust gas within the cylinder by not fully expelling it during the exhaust stroke.
Saving Fuel with ECU/OBD Tuner?
When we remap a vehicle, especially when fuel saving is the priority we focus on improving the low end torque in particular and widening the power-band as far as we can.
This increase in low end torque will mean less throttle pedal input is required to maintain cruising speeds, when fully laden or when on a gradient. It will also mean that the vehicle will be more comfortable in higher gears at slower speeds as well requiring fewer gear changes overall.
If you combine these factors with adjusting your driving style to make the most of the extra low end torque you will see an improvement in fuel consumption. This is most effective on turbo-diesel engines where the savings could be as much as 20%!
What do you actually modify in my vehicle?
We do not change any hardware in your vehicle, we just modify the operating parameters in the ECU’s program or ‘map’. In many cases the map stored on the ECU’s processor can be accessed via the on-board diagnostics port (OBD) in the vehicle, normally found under the dashboard. In some newer models the ECU will have to be removed from the vehicle and the casing opened, our technicians will then use specialist tools to read the original map straight from the processing chip.
The technician will then upload the original map to our map writing team who will adjust the parameters to maximise the performance, fuel economy or a clever blend of both. Depending on the vehicle and ECU type the remapping process can take under an hour and if at any time you wish to return your vehicles ECU to its original default settings, this can be done easily and free of charge as we always keep a copy of the original software as a backup.
What are the Advantages?
Modern engines recirculate some of their exhaust gases back into the engine with the aim of reducing emissions. This is the is the main benefit of the EGR system. The downside is that exhaust fumes containing carbon deposits are constantly being recirculated through the engine through time causing a build-up of carbon deposits in the intake manifold etc.
These deposits sometimes contribute to the failure of the EGR system itself. Replacement EGR valves can be expensive and in the case of high mileage engines the continual carbon build up can eventually lead to total engine failure.
Removal of the EGR system by Blanking off the exhaust input and reprogramming of the engine managment ECU results in lowered engine temperatures, improved throttle response and economy and also can lengthen engine life by reducing oil contamination and carbon deposits.