2 ms·
Yes, a common strategy is to inject more EGR (exhaust gas) into the fresh intake air. As EGR is already burned, it is inert, so it negatively affects the combus
by JorgeGT 11y ago
Yes, a common strategy is to inject more EGR (exhaust gas) into the fresh intake air. As EGR is already burned, it is inert, so it negatively affects the combustion, lowering the temperature. With lower combustion temperature you get less NOx... but less power for each amount of fuel, so your efficiency/performance is lower, and also non burned products (CO, C) increase. You then trap those with the Diesel Particulate Filter... it's a very complicated game with very small margins, that's the reason of so much cheating.
- thrownaway2424 11y agoSince this EPA action is about NOx, it seems VW will need to lower combustion temperature, leading to higher soot and therefore more particulate filter cycles. That will also increase fuel consumption.
- sokoloff 11y agoEGR on a diesel also terribly gunks up the intake manifold downstream of the EGR introduction point. For that reason (and the loss of power and efficiency), it's often defeated.