Friday, June 15, 2012

TDI is Totally Diesel

I have recently moved from the Audi side of the dealership to the Volkswagen side. It did this for a number of reasons, but the main one comes down to the fact that I could see myself buying a Volkswagen, while I could not see myself getting an Audi. The Volkswagens are extremely practical cars. I'm the kind of guy who, while I like power and performance, I'm really wowed by things like fuel economy and technology.

The most exciting thing that Volkswagen has for me is also the most commonly misunderstood: TDI Diesel engines. Diesel engines are available on a number of models including the Jetta and Passat. On the inside, they are just like their gas-burning brethren, the difference being that while driving the TDI versions, you will go to the gas station about half as often. Most cars have a range of about 400 miles on a tank of fuel, TDI Passat officially gets 795 miles, but most owners find that they do better than that.

This is hybrid level fuel economy without the batteries, the production and disposal of which make a Prius about as environmentally friendly as a Ford Explorer. Additionally, Diesels have more torque than regular gas engines, and torque is what pushes you back in your seat when you hit the gas hard. For example, the Passat TDI has 236 lbs/ft of torque at 1750 RPM, versus the Prius' lethargic 105 lbs/ft at 4000 RPM. (For comparison, a Mini Cooper Clubman gets 118 lbs/ft.)

If TDI is so great, why isn't everyone beating down VW's door to get them? Hybrid-like fuel economy, truck -like torque, and without the hybrid environmental and safety concerns? The answer is that Americans have certain preconceptions about diesel. They think it's noisy, smelly, slow to start up, sluggish, and expensive.

I would like to address all five of these concerns right here, so that all of my readers can get the record straight, then go beat down VW's door to get themselves a diesel.

Noisy and Smelly
A big gas pickup truck is noisy and smelly, but it runs on gasoline. When many people think of diesel, they think of either 18 wheelers or farm equipment. The noise and smell that those pieces of machinery have is not because of their fuel but because of their construction. A VW diesel sounds just like a regular engine (in fact, it is a little quieter than a regular Audi gas engine). As for smelly, unprocessed, diesel exhaust is worse than gas exhaust, which is why a TDI engine has a more complex set of exhaust scrubbing technology at work, making TDI a cleaner tailpipe than  many gas engines. The smell is slightly different, but you would certainly never mistake it for an 18 wheeler.

Slow to Start Up
This is one I got just the other day. He suggested that diesels were annoying because you had to wait for them to warm up before they would start. This is ridiculous, as TDIs start instantly, just like a car does. However, diesel engines do not have spark plugs, combustion is created with heat and pressure rather than spark, so what if it's very cold. How long will it take to start then?

This is a video from Medicine Hat, Alberta showing a Golf TDI starting when it is 30 degrees below 0. My gas powered car doesn't start that well at 30 below.

According to Motortrend's review, the Passat TDI goes 0-60 in 8.7 seconds versus the 2.5L gas engine, which is the standard Passat engine, which took 9.0 seconds to reach 60. How's that for sluggish.

A Passat SE TDI starts at $25,995, which is a little higher than the Passat SE 2.5 at $23,725. Diesel fuel here in Connecticut is about $4.00 per gallon versus $3.80 for 87 octane. (However if you are comparing a TDI to a sportier car which requires premium gas, you are looking at similar sticker price and similar fuel price, but this is to compare practically minded models.)

The average person drives about 12,000 miles per year and keeps a car for 5 years.

Additional Purchase Price$0$2200
Average Mileage2737
Cost per mile$0.14$0.10
Cost of 60,000 miles$8,444$6,486

So, how much more will a diesel really cost you, once you take into account fuel savings? Assuming gas prices do not change, assuming that bio-diesel technology comes to a grinding halt, and not including the fact that diesel engines last much longer than gas engines, the difference in total cost is $200. (Mention this post, and I'll discount any TDI on our lot by $200, so there!)

Please don't actually beat down the door. The door to the showroom is glass, so just open it gently and come on in. We've got TDIs for everyone.


  1. I wasn't aware you didn't need to plug in diesel engines anymore! (I used to have to unplug some customers' cars before I plowed their driveways. They got upset when I didn't plug them back in!)

  2. I have to agree with everything in this post. Thanks for the

    useful information.
    Improve Mileage

  3. ""

    12,000/year. Been hearing this, as you have, since I was a kid in the 60's, saw it here and wondered if it was accurate anymore...

    Nope! It's declined to around 7,000. A trend that should continue as public transit continues to grow after the failure of the large corporations selling gasoline and cars to solve congestion and pollution problems (though self-driving cars will change the dynamic very soon and greatly.)

    Self-drive aftermarket kits, (currently DIY is possible, but isn't turn-key,) will shove self-drive into all areas and all markets of transport from delivery vehicles (no driver!) to Transport (driver/engineer watchman) rapidly even into States where it's not been legalized (and there may well be States where there's no actual ban now, as well as those which specifically legalized it.)

    After all, what cop is going to pull over a vehicle which is driving both legally and safely?