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(OP)
It's now starting to occur to the British press that meeting NOx emisions targets through SCR (& Adblue) is a policing nightmare:

I thought (in simple broad terms), SCR was a shoo-in in USA, whereas we in Europe still had our hopes in EGR, taking the economony hit instead.

- Steve

It is a problem in North America, too, but the issue is usually not the AdBlue system but rather the DPF.

A friend of mine is a heavy truck mechanic, and these new emission control systems are driving him nuts. Post 2007 trucks are constantly having DPF-clogging issues. Another friend of mine has had trouble with the EGR system on his 2010 VW Golf, and just recently had the DPF replaced. The car has less than 100,000 km on it.

There are plenty of trucks running around out there with the DPF hollowed out ...

I think the emission-control legislation has mandated technology that was not ready for prime time, but try telling the politicians and enviro-freaks that.

I put 430,000 km on a 2006 Jetta ... last year before the emission control systems got nasty. No more diesels until the technology gets sorted out.

Just wait until particulate filters become necessary on gasoline engines. It's coming.

The freaks will say "get an electric car". Ya OK, my job frequently requires driving several hundred kilometers every day and I can't wait hours for a recharge (and that's assuming it is even possible at all), electrics are not there.

I believe the SCR fluid refill interval on a current US passenger car diesel is only every couple thousand miles. So why would this present a problem? As for a heavy commercial on-highway diesel engine, the pump price of DEF fluid is about $3/gal, and is consumed at a rate of around 3% of diesel fuel by volume. That extra$0.09/gal would not seem to be an undue cost burden for truck operators.

(OP)
My next car is unlikely to be diesel, the legislative/engineering/practicality balance is far from settled. My previous car was one of the last pre-cat gasolines, fortuitously bought, but very happy with that balance (all the prerequisites for a cat, but no cat).

As for $0.09/USG (est.) voluntary additional operating cost in the commercial sector (for zero operator benefit)? Sounds high to me vs a competitor that chooses$0.00.

- Steve

The EPA was rather hesitant to allow the use of DEF out of fear that it would not be refilled. They don't mandate the technology, only the tail pipe emissions. I don't think there is any alternate available technology that meets the current emissions standards. I believe CAT tried to go the ERG route and failed miserably.

I know most of the passenger car & light truck diesels in the USA give all kinds of warnings about the DEF being low and then start reducing performance to try to persuade the driver to fill it. The refill interval is about the same as the oil change interval in hopes that it will be performed at the same time. Removing the system would require something to defeat the sensors, probably not too hard to do. Here in the US it is against the law to defeat emission systems but there is next to no enforcement. I know my '79 Mustang spent it's entire life with a "test pipe" in place of its catalyst.

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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

2
there is no way to make a modern truck engine comply completely with present day emission legislation (meeting both the NOx and HC/particles requirements) without adding some extra equipment for exhaust gas treatment. engines can be designed to either meet the NOx legislation or the HC/particles legislation without any additional equipment, but not both.

thus you will see engines that meet either the HC/particles requirements fitted with a SCR for reducing the NOx emissions that need urea /Adblue for the conversion of NOx to N2 or engines that meet the NOx legislaton but not the HC/particles legislation that are equipped with some kind of soot filter that needs to be recycled occasionally. both systems can work well and also do cause problems occasionally. most european truck builders prefer the Adblue option because it allows the engine to run at a somewhat higher temperature (hence the NOx) that may reduce fuel consumption.

the link to the UK "Adblue removal service" talks about temporarily bypassing the Adblue system for "off road use". that may be legal in the UK as the present limits are not applicable to off highway vehicles - although it does not seem to be in line with the thoughts behind the emission legislation. bypassing the Adblue system is achieved by mounting a ECU that tricks the engine into thinking the Adblue system is functioning as it should...

diesel engines in passenger cars cannot (are not) treated in the same way. to start with NOx emissions usually are much less of a problem because most diesel engined cars work within a rather low temperature range. that same low temperature leads to problems with HC/particle reduction devices - they will not work without additional hardware. Peugeot introduced a HC/particle reduction system that uses a cesium based fuel additive that acts as a catalyst to lower the operating temperature needed in the particle trap by about 200 degrees Celsius making it possible to burn off the soot when required. no other car manufacturers have taken over that idea, most of them nowadays have found a way to raise the temperature of the exhaust gas in the converter to the required level by introducing a injector in the exhaust somewhere between exhaust manifold and particle trap that injects some fuel that is ignited by the exhaust gas raising the temperature sufficiently for recycling the particle trap.

all systems seem to work well when maintained as advised, although a occasional failure may occur. a lot of drivers however still seem to see no need to bring down emissions and thus like to complain about the added complexity and cost of newer designs.

I have seen a definative surge of people using services like https://www.adblueremoval.com for many of my Truck mates.
The obvious question is if they are to continue to sell the services for "off road" use when will the laws be changed to stop this happening.
I can see this whole emissions war only getting bigger as the new wave of eco cars now released are brought out.

http://www.thesundaytimes.co.uk/sto/news/uk_news/a...
I also remember seeing this and i asked the lads I worked with if thss was true.
Seems like Department for Transport made a big loophole for this to happen...

Also can anyone confirm with the new VW motors coming out that they have to now service the adblue system every 6 months?

Ta - TTips

The AdBlue system does not have a prescribed service interval; you just have to keep the tank filled.

Some VW models had issues with the AdBlue system freezing up in very cold winter weather. The system has heated lines, but evidently it wasn't enough.

The new Ram 1500 Eco Diesel has had problems with both the DEF freezing and the intercooler collecting water and/or freezing. Many reports of trucks going into limp home mode in both Canada and New England. This truck was selling well above expectations, they increased the build rate to20% of production. I expect this to fall with the drop in gas prices and these freezing problems.

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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

VW has gone through intercooler-freezing, too. The new EA288 engines - and in fact, all of VW's new-generation turbocharged engines whether gasoline or diesel - have gone to a liquid-cooled intercooler with its own coolant loop, electric pump, and radiator, because that way they can regulate the temperature to stay above freezing.

I'm back to conventional, port-fuel-injected, non-turbo gasoline engines until all this gets figured out.

(OP)

#### Quote (BrianPetersen)

I'm back to conventional, port-fuel-injected, non-turbo gasoline engines until all this gets figured out.

Hear hear. Gasoline engine electrics (their weak link) are strong enough now that the reliability and longevity of (mechanical fuel injected) diesel isn't a benefit.

- Steve

I don't think gasoline engine electrics has been a weak link since the passing of the Prince of Darkness.

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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

·The Lucas motto: "Get home before dark."
·Lucas is the patent holder for the short circuit.
·Lucas - Inventor of the first intermittent wiper.
·Lucas - Inventor of the self-dimming headlamp.
·The three position Lucas switch - Dim, Flicker and Off.N
·The Original Anti-Theft Device - Lucas Electrics.
·Lucas is an acronym for Loose Unsoldered Connections and Splices.

and to all, note that the prevoius post (not this one) was made by a former Lucas employee, so he should know very well of the Prince of Darkness.

(OP)
I was thinking more of the ignition system, not the lights & wipers. Modern diesel FIE has just as many electrical parts to go wrong as SI systems.

- Steve

My brother-in-law had a 1970s Dodge Aspen that wouldn't start if it was raining or foggy.

(OP)
It was a long long time ago (that I was a Lucas employee). Not guilty of any darkness though...

- Steve

You forgot
Why do the English drink warm beer - they have Lucas refrigerators.
Who is the most nervous man in the world - the one with the Lucas pacemaker.

My one and only personal experience with Lucas electrics was the Lucas magneto on my 1972 Rickman dirt bike. It produced a spark you could almost see in the dark. My 1974 with Bosch CDI ignition was much better. My Lucas employment was in the CAV diesel fuel injection division. We did have a graph of universal entropy which showed a large spike coinciding with the birth of Joseph Lucas.

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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

Dgallop,
I drive a 53 year old Jensen built Volvo, with Lucas electrics, based on your, and djhurayt's comments I wonder how it made it that long ?
B.E.

You are judged not by what you know, but by what you can do.

you should probable be buying lottery tickets
or wondering parking lots looking for lost wallets
at the very least you better go knock on some wood so you don't get stranded tonight

Berkshire - Where are you, England? I find (at least with older cars) that they do well in their home areas, less well when they were exported. Just like old Detroit iron was suited for the mid-west flat lands but hopeless on English country lanes, Lucas electrics seemed quite adequate in England where it never gets all that hot or cold and you can't drive very far. Their in house publications were always touting some quality recognition or satisfaction survey. I was always surprised how clueless the management was about their reputation in the US.

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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

(OP)
"Their in house publications were always touting some quality recognition or satisfaction survey."

No such boasting when a batch of starter motors were returned once, because they had the wrong number of teeth on the pinions

- Steve

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