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Comment by makomk | Hacker News Reader

Not terribly surprising. Their engineers are competent, it's just that the US (where diesels are less popular) set some rather unpleasant requirements for diesel cars, in particular insisting that they couldn't require the diesel exhaust fluid tank to be topped up by the end user and setting lower NO2 limits. In order to meet these conflicting requirements, VW cheated. I think some of the VWs they tested actually have the same engine and emissions control system as some of the US models that cheated, just without the defeat device intended to reduce exhaust fluid usage.

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> in particular insisting that they couldn't require the diesel exhaust fluid tank to be topped up by the end user

Not being rude, but I'm having trouble parsing that part of your comment.

Do you mean that the US authorities won't let diesel car owners re-fill the diesel exhaust fluid tank by themselves, i.e. the re-fill must be performed by a dealer?

Also is the DEF tank just a US thing? I'd never heard it before (UK resident here).

The DEF tank is a global thing – ever heard of AdBlue etc?

But yes, the issue is that the US requires dealers to refill them. And also sets a limit for how often refill cycles may happen. And the weight of the tank sets a limit on how large it may be.

The result is simple: Small Diesel cars can’t exist legally in the US.

This is all completely new to me (and probably most folks unless they're running around in brand new diesel vehicles). The last diesel car I owned was a 1998 (Euro-2 standard when NOx emissions were more relaxed - so no DEF required [0]) Ford Mondeo which I disposed of in 2006 when the timing belt snapped ruining the engine. Since then I've owned older petrol engined high mileage "bangers" so I would never have encountered DEF unless I won the lottery and fancied a new Landrover :)

[0]: https://en.wikipedia.org/wiki/European_emission_standards#Em...

>The result is simple: Small Diesel cars can’t exist legally in the US.

And that is, of course, intentional. To keep some of the foreign competition away.

Because American companies can't make diesel cars?

They do with reasonable success in many parts of the world, so I'm not sure what GP was trying to claim.

Because American companies don't make diesel cars.

Aside from trucks, that is.

I tend to keep up on cars, and I can't name any American-brand, small diesel off the top of my head from the last 30+ years, aside from last year's Chevy Cruze.

Edit/clarification: I'm speaking strictly of the American market. If American companies make small diesel cars for international markets, it's not at all relevant to discussing small diesel cars in the US.

There were multiple unfortunate diesels in the 1980s. My first thought was "Ford Escort" and a bit of searching confirms that there was one (Mazda made the engines though).

Ford makes them though, but only in Europe, and they are not particularly strong in diesel at that. Both Focus and Mondeo are available as diesels. And even Fiasco...sorry, Fiesta.

GM don't sell Opels in the US, although they could re-badge them as Chevrolets.

> Ford makes them though, but only in Europe, and they are not particularly strong in diesel at that

I disagree, certainly from a UK perspective.

Most modern Ford diesel engines are the product of the collaboration between Ford, Citreon and Peugeot [0][1].

Ford diesel Focus and Mondeo's are hugely popular and are quite reliable, reasonably sporty and fuel efficient things. My dad's last three Fords (Focus, Mondeo then Focus) were all diesels and he loved them. Virtually everyone I know that own's a Focus has one of the diesel versions.

[0]: https://en.wikipedia.org/wiki/Ford_DLD_engine

[1]: https://en.wikipedia.org/wiki/Ford_AJD-V6/PSA_DT17

Yes, I don't disagree, you can buy a Focus, but I said Ford is not particularly strong in diesel. They work with PSA to get the engines. Still, a smaller percentage of Ford's European cars are diesel, compared to all major German and French brands, Volvo, Nissan or even Dacia.

Replying to maxericson downthread:

To the extent that consumers remember crappy American diesels, I would say the most infamous is the Olds diesel. GM took a (not so great) SI engine and turned it into a CI engine.

Because keeping diesel cars away from the US market leaves them with a bit less competition.

American companies make some diesel cars in other markets (Ford, and GM with its Opel and Vauxhall brands) but they have a significantly smaller market share in diesels than in gasoline engines.

Easiest way to look at it is this: http://www.statista.com/statistics/425324/eu-car-sales-share...

You'll find Opel, Vauxhall and Ford towards the lower end of the table.

> Because American companies can't make diesel cars?

If they can, they're keeping it a secret.

My family bought a 1982 GM diesel. It was an absolutely atrocious car. Everyone that bought these diesels got burned. Lessons were learned.

"Everyone knows" that American buyers won't buy a diesel, just like "everyone knows" that American buyers won't buy a wagon.

This page from Land Rover has a good overview, apparently it's a new requirement in Europe (I've also never heard of it before):

http://www.landrover.co.uk/ownership/euro-6-emissions-standa...

"A third warning indicates when 515 miles are left and also warns that the DEF tank needs re-filling or the vehicle will not be able re-start when the distance countdown reaches 0."

Wow.

"The engine will only start again when the DEF tank is re-filled."

And thus the the "faulty DEF sensor" malfunction is introduced into our car fault lexicon.

There's no limp mode?

A truck mechanic told me that drivers have been rumored to urinate in the DEF tank to bring the level of urea up to the point that it can be driven.

Well I suppose that's unintended comedy in the naming then.

Sounds like an urban legend. DEF is 325 g/L urea. Urine is roughly 9.3 g/L urea. Not a great substitute.

I think they're taking the piss.

I'm pretty sure that owners can refill the tank by themselves, but manufacturers are required to have a big enough tank that it can be done by the dealer as part of the regular servicing schedule. The tank itself not so much a US thing as it is a modern diesel car thing; it's part of the emissions control system on I think most new diesels.

Wow, I hadn't heard this. What a counterproductive, idiotic piece of regulation.

It's not an idiotic regulation. If you fit a tiny reservoir that needs to be topped up every week then most customers wouldn't bother, and the car would be spewing extra toxins. So you have to make it large enough that normal servicing will ensure it is filled.

Using "limp mode" with warnings to ensure the tank stays filled (and the car does not run at full throttle unless it is filled) is a much better solution.

When the sales guy told me the tank only had to be filled at service intervals, it sounded strange. People on the TDI forums thought it was just because VW didn't want to scare away customers with an extra thing to do, but you can buy the stuff at any gas station and pouring it into the tank is not difficult.

When the scandal broke the assumption was that they mistuned the DEF cars out of arrogance, and again to avoid spooking customers with extra maintenance.

Now it sounds much more like they tuned it that way because this regulation would have crippled the car with an enormous DEF tank otherwise. It is possible that such a regulation combined with a 10,000 mile service interval only makes engineering sense on mid-size trucks or larger.

This doesn't have anything to do with them failing to build a working LNT solution and cheating with those previously, of course.

It's very simple: make the car so that if the tank hits empty, the car doesn't run any more.

If you think that's a problem, then please explain why this isn't also a problem for the gas tank. I don't know of any cars which will continue to drive (but spewing extra toxins) when the gas or diesel tank is empty.

Customers don't seem to have much of a problem topping up their diesel tank every week or two....

The legislation is in place because consumers are lazy.

"Limp mode" is a much better solution, switching that on will basically guarantee the fluid gets refilled in short order.

And actually I'm not so quick to assume this is only a stupid decision either. Hanlon's razor still applies but there is also a distinct possibility that this regulation was "encouraged" as a play to make small diesel cars less competitive.

It's a different solution, but I don't know if it would be better. How do you think it's better?

VW doesn't want their cars going into limp mode. They don't want customers calling up asking why their car is acting funny. They don't want to increase the maintenance load on their customers. They don't want customers coming in for unnecessary service appointments (especially for stuff they wouldn't be able to charge for). Making a tank big enough to last as long as the motor oil seems like an easy, low tech solution. Sometimes simple is better.

See my reply above, I'm inclined to believe that storing enough DEF for correct dosing through a 10,000 mile service interval may not be feasible for a small car.

After hearing about this regulation it seems an obvious reason why they would keep the cheat enabled even after adding a DEF system.

> I'm inclined to believe that storing enough DEF for correct dosing through a 10,000 mile service interval may not be feasible for a small car.

It is feasible and they already do it.

Do you mean VW? All the speculation I've read is that the DEF cars are also being recalled because they don't use the correct dosing.

Or do you mean the Chevy Cruze? They must have some strategy that works (so far).

What they are going to do during the recall is different for the various generations of cars.

Some of the VWs are getting bigger DEF tanks. For the cars that this isn't an option, I don't think VW has said exactly what they are going to do. They could just disable the cheating mode on the software. Fuel economy and performance would suck, but the emissions would be at acceptable levels.

I haven't heard anything about the latest agreement, other than that it will involve a buyback offer, unspecified fixes, and/or compensation. You don't have a source do you?

There's been a lot of speculation all along, will they retrofit DEF systems, will the cars just get super unreliable because the systems can't handle prolonged legal operation, etc.

No, I don't have a source I can point you to. I was talking to a Audi mechanic last weekend. He told me that 2015 cars were pretty much unaffected and will likely only get a firmware tweak.

2013-2014 cars need to hold 1/2 gallon more exhaust fluid and apparently that's doable (and also new firmware).

Older cars are a bigger problem and will likely get a combination of fixes but in the end, they are going to be louder, fuel hungry cars after getting "fixed".

The oldest cars will likely get owners a buy-back offer because the depreciated value is lower than the cost to fix.

OK thanks.

>He told me that 2015 cars were pretty much unaffected and will likely only get a firmware tweak

And what exactly will this firmware tweak do? If it decreases performance or fuel economy, then that isn't acceptable. The customer bought the car because it advertised X horsepower and Y mpg; if the firmware tweak changes that, then that's false advertising and the company needs to refund their money in full.

VW is offering some compensation too. There are also a bunch of big lawsuits chugging along. If you aren't happy with the settlement VW is offering, join one of the lawsuits. Those are pretty much your only options.

Luckily, I don't own a VW, I'm just pointing out how this is a scam. If I were a VW customer, I'd be really pissed. I'm really glad I passed on VWs and bought a Mazda instead.

What's really stupid is that it sounds like they should be able to get the advertised power and economy with the required low emissions simply by using more DEF. I'm assuming the DEF liquid isn't too expensive here, but if they just made it so you needed to refill it every 1000 miles, that should solve the problem. Heck, why can't they just make it available at gas stations too?

Having this idiotic notion that only dealers should be able to refill the stuff, and that it needs to be done at 10k intervals, is what's making it impossible.

Why not require that cars must be able to carry enough fuel to drive 10,000 miles while they're at it? It makes as much sense.

My dad has a US Volkswagen diesel. He's told me he can refill the urea tank, but he can't reset the computer to tell it the tank was filled, so there's very little point for him to actually refill it. His car will stop working unless he brings it into the dealer, one way or the other.

See, this is a great example of how our regulators have failed miserably. This kind of practice should be outright banned. There should not be anything on a car that requires you to take it to a dealer to reset; any competent mechanic should be able to do any service on the car, and not need a special dealer-only computer system to make the car recognize the service.

My car recognizes when I refill the tank. Not sure what is going on with your dad's car.

Has he tried getting an OBDII reader (they're really cheap) and resetting the fill status himself?

After looking into this the only thing I can find is a reference to 4,000 mile capacity[0], way less than a TDI service interval. Maybe they mistuned it just so customers wouldn't have to pour a bottle of stuff into the tank, which would have been an awful idea. Or maybe the catalyst they used isn't sufficient to meet US NOx standards with the optimum fuel-air ratio, I guess we will have to wait and see.

[0]https://www3.epa.gov/otaq/documents/nonroad/420f14017.pdf

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