Originally posted by Cristi_Xp
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Este adevărat că pentru mine ansamblul EGR și DPF tot din sistemul de filtrare fac parte, eu le numesc la comun.
Eroarea este legată de necitirea cu atenție a ceea ce spun. VW a făcut ce spuneți în legătură cu secvențele de test.
Însă, alți producători germani sau francezi nu au făcut asta. Ci foloseau un sistem de "thermal window". Regulile erau făcute pentru a testa sistemul de filtrare în temperaturi de 20-30 C. Din motive de protecție a motorului, toți producătorii opreau EGR-ul în afara acestui interval, fiecare după puteri. Unii sub 10 C, alții sub 17C. Unii peste 35C. Argumentul tehnic fiind prevenirea colmatării turbinei.
Audierile din Parlamentul European și răspunsul Renault, dacă tot vreți să fiu/fiți riguros, respectați faptele.
4. During recent national investigations, manufacturers including Renault admitted to using so called “thermo windows” to switch off emission control systems under certain ambient temperatures in order to protect the engine. It has become clear that there is a broad range of temperatures used for lower switch-off limits (e.g. below 10°C - Daimler or below 17°C - Renault and Opel). This suggests that the setting of these temperature limits are rather arbitrary. Please explain the discrepancy in temperature limits used by car manufacturers to justify switching off emission control systems (including EGR). What are the operating conditions of those emission technologies used in your fleet (including minimum and maximum ambient temperatures, in case there is a maximum and a minimum) which do not damage the engine, or lead to accident or unsafe operation? Please distinguish according to the abovementioned technologies. Are these limits really needed to protect the engine and at which ambient temperatures? Why did you agree to recall and adjust 15.000 vehicles if you had acted within the law? Why does the U.S. EPA only allow switch-off of EGR under only minus 4 degrees Celsius?
Exhaust Gas Recirculation (EGR) has been widely used in Europe since the late 90s as a “state of the art” means to reduce NOx “engine out” emissions (ie. before after treatment) of Diesel engines.
Regarding Renault Euro6b vehicles, at the moment, EGR flow is reduced (not cut) below 17°C, and above 35 °C of engine inlet air temperature. This “temperature window” was set by Renault in the years 2000-2005 to avoid severe reliability and safety issues we faced with a high rate of incidents for customers.
Each OEM has set a temperature window adapted to its engine and components characteristics and lay-out. Thermal conditions in the engine bay is a key parameter for several issues encountered with EGR systems, as the physical or chemical phenomena’s are strongly depending on temperature. Temperature in the engine bay and at engine inlet, for a given ambient temperature depends on a lot of parameters (engine and engine bay lay-out and driving conditions). As a whole, we believe it explains the variety of temperature limits among OEMs.
In order to better take into account various driving conditions, and prepare for the future “Real Driving Emissions” protocol coming with Euro 6d, Renault has launched in July 2015 technical analysis and actions aiming at expanding this temperature window for vehicles already launched in production and future products.
We took advantage of improvements done on the components since the years 2000-2005 and more recently, better knowledge of the limits thanks to the market feedback we could analyze now to judge real life reliability of improved components and tuning, put in the market after the 2000-2005 (“black period” on EGR failures)
After a specific validation process that we had carried out since July 2015, we can expand the EGR temperature window to 10-45°C for current models, and up to 5-60°C for new products launched from now on.
This improvement will also be proposed to all our customers driving a Euro6b vehicle, as communicated in medias in April 2016.
Regarding the “15.000 vehicles”: see question 1 ; these vehicles (actually 11.500) will be recalled because testing have shown they were non-compliant with emissions limits over type 1 test (NEDC), due to a calibration error at the beginning of production of these models. This is not linked to “thermo window”
We are not present on the US market and thus we are not able to make relevant comments on the US regulation.
Exhaust Gas Recirculation (EGR) has been widely used in Europe since the late 90s as a “state of the art” means to reduce NOx “engine out” emissions (ie. before after treatment) of Diesel engines.
Regarding Renault Euro6b vehicles, at the moment, EGR flow is reduced (not cut) below 17°C, and above 35 °C of engine inlet air temperature. This “temperature window” was set by Renault in the years 2000-2005 to avoid severe reliability and safety issues we faced with a high rate of incidents for customers.
Each OEM has set a temperature window adapted to its engine and components characteristics and lay-out. Thermal conditions in the engine bay is a key parameter for several issues encountered with EGR systems, as the physical or chemical phenomena’s are strongly depending on temperature. Temperature in the engine bay and at engine inlet, for a given ambient temperature depends on a lot of parameters (engine and engine bay lay-out and driving conditions). As a whole, we believe it explains the variety of temperature limits among OEMs.
In order to better take into account various driving conditions, and prepare for the future “Real Driving Emissions” protocol coming with Euro 6d, Renault has launched in July 2015 technical analysis and actions aiming at expanding this temperature window for vehicles already launched in production and future products.
We took advantage of improvements done on the components since the years 2000-2005 and more recently, better knowledge of the limits thanks to the market feedback we could analyze now to judge real life reliability of improved components and tuning, put in the market after the 2000-2005 (“black period” on EGR failures)
After a specific validation process that we had carried out since July 2015, we can expand the EGR temperature window to 10-45°C for current models, and up to 5-60°C for new products launched from now on.
This improvement will also be proposed to all our customers driving a Euro6b vehicle, as communicated in medias in April 2016.
Regarding the “15.000 vehicles”: see question 1 ; these vehicles (actually 11.500) will be recalled because testing have shown they were non-compliant with emissions limits over type 1 test (NEDC), due to a calibration error at the beginning of production of these models. This is not linked to “thermo window”
We are not present on the US market and thus we are not able to make relevant comments on the US regulation.
. D'aia , dupa ce si-a luat-o VW, mai toti producatorii, inclusiv Renault , recheama pentru resoftare motoarele diesel. Sa le faca sa sufle O3 pe teava de esapament ;)
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