Driving into Paris a few years ago in a Peugeot diesel hatchback, I became lodged in a long line of traffic. I started coughing violently. It was so bad, I nearly couldn't drive. Thankfully, I had a bottle of water, which helped. I blamed diesel fumes.
Pollution is one reason why the diesel engine has perhaps peaked at 50 percent of new-car sales in most of Europe.
Politicians are criticizing diesels. Gasoline-electric hybrids are gaining momentum as a way to reduce CO2 instead of diesels, particularly at the Germany luxury brands. Three-cylinder engines are emerging as another method. Diesel-electric hybrids are feasible, but they are expensive.
In parts of London, the air quality is so poor, The Independent newspaper reported, that children's lungs are being stunted. In Paris, the mayor wants diesel banned from the city by 2020.
Because diesel fuel burns at a higher temperature than gasoline, the exhaust has more soot, which contains carbon combined with sulfate, nitrate and metals.
Electrification may be the next step in cleaning up diesel. Using an electric motor to reduce the load on a diesel engine could indeed reduce emissions, says Tom Watson, the former chief engineer for the Ford Escape hybrid who now works for Johnson Controls as a technical fellow in powertrains and vehicle systems.
He said diesels produce more pollution during acceleration. An electric motor can reduce these loads.
The Peugeot 3008 uses an electric motor to drive the rear wheels while a diesel powers the front wheels. But all those extra parts add cost.
Smaller, turbocharged gasoline engines are also drawing people out of diesel-powered cars. Ford's 1.0-liter three-cylinder engine has been drawing customers out of diesel cars, despite the fact that gasoline is far more expensive than diesel fuel in Europe.
Alternatives to diesel are getting better each year. It looks like diesel has peaked in Europe.