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Have Bosch Cleaned up Their Act?

Diesel engines have had a tough time of late, what with all the lying and cheating from VW and others caught up in the Dieselgate scandal.  It was with some skepticism then that I read the news that Bosch (who were central to Dieselgate) are claiming to have solved the problem of diesel NOx emissions.

Unlike gasoline (petrol) engines, the diesel drivetrain uses injection of the fuel to initiate combustion, and they time this so that it operates at a high thermal efficiency.  This gives diesel powered cars and trucks excellent fuel economy, but comes at the expense of air quality, with diesel being prone to the formation of soot and NOx.  Maintaining high fuel efficiency while keeping down emissions has been a key challenge for diesel automobiles, and was what drove VW to criminally conceal the true on-road emissions of their vehicles.

Now Bosch are making bold claims that they've made a breakthrough in diesel technology that can meet strict EU emissions standards, saving the diesel automobile.  This breakthrough doesn't involve any new engine hardware though, and instead appears to focus on optimising the operating conditions for various stages of the engine and the exhaust system.  What isn't being discussed is how this new control system influences engine efficiency - remembering that the emissions vs efficiency trade-off is what put diesels on the chopping block to begin with.  Their failure to mention the effect on engine power and torque is what makes me doubt that this is truly a breakthrough; it feels more like a PR exercise from a company with a checkered past trying to promote a technology in which they are heavily invested.

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