New release - Audi Golf Passat Seat 2.0 Ltr Tdi Engine
EGR Delete Kit available now
|Motor sport versions are available for complete removal of EGR units on the 2.0 Ltr Tdi engines.|
Please enquire for price and availability
EGR replacement kits now available for most VAG group engines, including BMW & LandRover TD5
Original EGR Valve 1.9 Tdi 130 / 150 Engine
Original EGR Valve 1.9 Tdi 90 110 Engine
EGR Power Pipe Upgrade @ 57 mm Bore
EGR Power Pipe Upgrade @ 51 mm Bore
Understanding The EGR System.
The Exhaust gas re-circulation is incorporated in an attempt to reduce the level of nitrous oxide being emitted through the exhaust system. To achieve this a proportion of the exhaust gas is diverted back from the exhaust manifold to the inlet manifold via EGR valve unit to mix with the inducted charge, which is controlled via the solenoid which can be found on VW models at the back panel within the engine bay. On most models EGR solenoids are controlled via the engine ECU incorporating a vacuum source from the vac pump which serves the braking system.
The system works well as far as reducing the oxides of the nitrogen on a new engine, but in general on older engines of over say 2 years (35,000 miles), the effectiveness is compromised by the sludge build up inside the inlet manifold. This further reduces engine performance and airflow, which in turn reduces combustion efficiency and increases other unwanted emissions, principally Co2 and particulate emission. The sludge is a combination of oil and exhaust emission (soot) meeting at the EGR valve inlet, the oil can be found leaking from the front bearing of the turbocharger (compressor side) but mainly from the breather system which is directly connected into the induction tube between the air filter and turbocharger on a tdi engine. Many people think that simply replacing an EGR valve will solve the problem; well that's simply not the case. As the turbo bearings continue to wear from brand new and the breather system left connected the engine will continue to discharge oil into the turbocharger inlet, which then leads up into the inlet manifold/EGR valve.
The EGR valve itself is generally a reliable part and can last the life of the engine, the only way of solving the problem of sludge build up is to ultimately renew the turbo (if has started to leak oil) and fit a separate engine breather system as shown in Fig.02 below.
"All EGR systems reduce air flow, combustion efficiency and consequently engine power"
From the point of view of obtaining optimum power output, it is obviously detrimental to introduce hot exhaust into the inlet manifold, even if this is only under light load conditions. The associated pipe work restrictions and the over run (anti judder) valve also contribute to this. Systems with a water circulation system will only go part way to reducing foreseen problems. Apart from these facts, on older engines there are increasing failures with leakages from the EGR valve and to replace one can cost more than £150.00 or more.
Fig.1 Shows EGR Kit for a VAG group engine - Volkswagen / Audi / Seat / Skoda
EGR COOLING SYSTEMS
The cooler serves to decrease the temperature of the recirculated exhaust gas. Typically, the cooler comprises a cylindrical housing, a plurality of pipes installed into the housing, a chamber formed in the housing, and a coolant pipe. Another EGR system employs a plate-type distributor formed by combining two plate members, so that the mechanical complexity is significantly reduced.
However, such EGR systems are disadvantageous in that the cooler results in an increase in the number of components and mechanical complexity of the system. Furthermore, the EGR systems are disadvantageous because the systems require sophisticated work in connecting the coolant pipe to the EGR distributor. Because the recirculated exhaust gas is supplied to the cylinders through a pipe, to which each cylinder is connected in series, the amount of exhaust gas recirculated to each cylinder is not uniformly distributed. Due to the unregulated distribution of the recirculated exhaust gas, the efficiency of the EGR system is lowered.
In order to comply with 2002 EPA emissions regulations, cooled exhaust gas recirculation (EGR) will be used by heavy-duty (HD) diesel engine manufacturers as the primary means to reduce emissions of nitrogen oxides (NO\dx ). A feedforward controlled EGR cooling system with a secondary electric water pump and proportional-integral-derivative (PID) feedback has been designed to cool the recirculated exhaust gas in order to better realize the benefits of EGR without overcooling the exhaust gas since overcooling leads to the fouling of the EGR cooler with acidic residues. A system without a variable controlled coolant flow rate is not able to achieve these goals because the exhaust temperature and the EGR schedule vary significantly, especially under transient and warm-up operating conditions. Simulation results indicate that a controlled EGR cooling system can maintain the EGR cooler outlet exhaust temperature at 130\mP8\mDC, as compared to 110\mP60\mDC for an EGR cooling system without coolant flow control. A system with controlled EGR cooling combined with a controlled engine cooling system indicates decreased warmup times for fast warmup of aftertreatment devices, decreased power consumption, and better engine temperature control.
NEW Release for 2009 - Volkswagen T4 Transporter 2.5 Tdi EGR Power Pipe Kit