By: Kristi Bannen
Initially I dreaded the thought of testing a diesel vehicle. Yet, I have to be honest, my perception was far from reality regarding today’s diesel. Like most people, I figured the diesel Volvo S80 I tested would be smelly and noisy and no fun to drive. On the contrary, this car was equipped with the Bosch Common Rail System for diesel engines which represents significant advances in diesel technology.
I’ve rated some key features
based on diesel advancement on a scale of 1 to 10, 10 being the highest rating.
Fuel Availability 4
Overall Impression 8
Whether I was starting the car or just driving, the engine was consistently very quiet. Even passengers in the car didn’t know it was diesel unless I told them.
As for the fuel availability, I really had to search for stations that had diesel and I had to remember them for future use. And when I did find diesel pumps, they were often dirty and covered with diesel residue. While I didn’t like that, it was still a fair trade since I didn’t have to fill up as often. Fuel economy is definitely a bonus of diesel.
Also, It’s been entertaining watching the gas station attendants’ reactions to the diesel car. The manager at one of the stations came out to make sure I knew I was about to put diesel fuel in my car. When I told him my car was diesel, he still didn’t believe me. He searched the entire car looking for “something” that proved it was diesel and just shook his head as I filled it. And at a different station, I went in and told the cashier what pump I was at, and she said, “dear, that’s diesel, you must mean another pump,” and when I told her that was the pump I needed, she apologized and
said she just wasn’t used to seeing a diesel car, let alone a woman driving a diesel. She said I wouldn’t have surprised her as much if I had pulled up in a big truck.
As for the smell, the only time I could smell the fuel was when I started the engine from a cold start. Otherwise, it was really nonexistent. I also learned why the engine felt like it was racing more when I first would start the car. The idling speed is higher then normal with a cold start initially to help minimize exhaust emissions and it does that by bringing up the engine’s exhaust purification system to its correct working temperature as quickly as possible.
Today’s diesel does have reduced emissions too. Less carbon dioxide is released into the air and that means less pollution. Plus, the fuel burns more completely through the super-high pressure fuel injection process Bosch uses which eliminates the unburned fuel that causes pollution.
Comparing the diesel Volvo S80 to other similar gas powered cars in terms of performance; the diesel performs just as well and is quite smooth and fun to drive.
Overall, the challenge is really changing old perceptions versus the new reality and advancements made with diesel engines.
Now, for those of you more technically inclined or interested, here is how Bosch explains the highlights of its Common Rail System:
· Injection pressure and injection event control are independent of engine speed or position
· Injection pressure and injection events can be optimized independently
· Multiple injection event capability
· Alignment of pilot and post injection events to emission or after-treatment system requirements
· Suction metered pumping principle for improved fuel consumption
· Applicable to light, medium and heavy-duty vehicles
· Delivers high torque at low engine speed
· Applicable to a variety of cylinder configurations
· Potential solution to the future emissions challenge
· Flexible design can be easily integrated into diesel engine
· Excellent application flexibility relative to injection pressure, timing, pilot and post-event control
· Proven application and manufacturing experience. Bosch was first to market with Common Rail for passenger car applications
· Delivers quiet, high-torque, low-emission and efficient diesel engine performance to the consumer
But, our test continues as we move from the Volvo to an SUV. More to come!