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Originally Posted by Autobahnschleicher
1. Modern diesels work about the same as oldschool ones in that regard, but they do add some EGR especialy under low load to keep NOx down
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Good to know!
Quote:
Originally Posted by Autobahnschleicher
2.That's what the EGR is supposed to do, the filling intervalls can depend on driving conditions though.
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Makes perfect sense.
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Originally Posted by Autobahnschleicher
3.You might not even notice the car initiating a regen cycle when driving on the highway as it just injects a little more fuel after combustion to get the exaust gas temps up enough.
Plus highway driving means you might not even need regen cycles at all as there your EGT goes up sufficiently on its own.
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Right. I've read that a good highway blast is good for modern diesels from time to time, and that's probably why. This car enjoys the left lane anyway.
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Originally Posted by Autobahnschleicher
4. Yep, diesels can be very efficient, yours is actualy not that efficient by diesel standards.
Take a look at the Passat 1.9 TDi or a Lupo 3L
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I could also ride a scooter.
I'm just comparing this car to its gasoline powered siblings, or other comparable cars with gas engines. It was only available in this AWD 3L six configuration in North America, but in Europe is was available with several four cylinder diesels that are all quite a bit more efficient than this.
The newest Passat TDi sold in North America was the 2015 model, and the most fuel efficient version was EPA rated at 30 MPG City, 42 MPG hwy, 34 MPG combined:
https://www.fueleconomy.gov/feg/Powe...=1&rowLimit=50
Compare that to the 535d at 26/38/30 combined:
https://www.fueleconomy.gov/feg/Powe...=1&rowLimit=50
Compared to the 535d the Passat TDi is smaller, 600 lbs lighter, only FWD (no AWD option), 118 hp less powerful, 3 seconds slower to 60 MPH, and doesn't even have an automatic transmission (the auto drops it to 33 MPG combined). For an additional $12.50/month in fuel compared to the automatic TDi, I'll take the 535d. Especially in Canada where AWD is important three months of the year.
A more even comparison to that Passat TDi would be the 2016 BMW 520d, the same car but with a 184 hp 2L diesel. Compared to the 520d XDrive the Passat TDi still has all the disadvantages listed above, except it's only slower to 60 by about 1/2 a second. Extrapolating from published European data the 520d would test about the same as the automatic equipped Passat TDi - 33 MPG combined.
All that said, if the Passat TDi is considered an efficient car, the diesel BMW 5-Series is a very efficient car since it seems to do more with the same amount of fuel. Shame more European diesel models were not made available here in North America.
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Originally Posted by Autobahnschleicher
5. Diesels hate the cold.
As they are so efficient under low load and move that much air, they take a long time to warm up.
In idle they might not even heat up at all, so if it gets very cold where you live, consider a block heater.
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I did quite a bit of research on this car before buying, and a good chunk of that was looking into winter performance. It didn't seem to be an issue, and based on my experience last winter it doesn't look like it will be.
Ottawa can get pretty cold, though last year was warmer than usual. We had a few nights down to -25C (-13F) and I'm pleased to report it started absolutely perfectly each and every time. It will ask that you wait 5-6 seconds for the glow plugs to warm up, then it will crank and start like a champ. It did sputter/vibrate once as if one cylinder wasn't firing, but a blip to 1500 RPM solved that quickly. If we have a more typical winter this year I hope the same remains true at -30C (-22F). If so, it gets a huge gold star for cold weather insensitivity.
With heated steering wheel and seats, engine warm-up time isn't as much of a concern. Having said that, I'm
absolutely shocked at how quickly this thing warms up. I'm not 100% sure, but I think there must be a resistance heater in the HVAC because it's blowing warm air within a couple minutes of setting off - but that's not the impressive part.
What really gets me is how quickly the engine gets up to temperature. The dash doesn't have a water temperature gauge, it has an oil temperature gauge, and after my easy ~22 min 22km (14 mi) commute to work the oil temp is right in the middle of its operating range (roughly 110C or 230F). On really cold mornings the oil temp doesn't quite make it to the middle of the gauge, but since oil temp generally trails coolant temp I'm reasonably confident the engine is fully warm. That's with the HVAC set to auto to prioritize heat in the cabin, and fuel efficiency seems to be not far off what I see in warmer weather to boot.
Winter heat is just an absolute non-issue with this car, which is in total contrast to my last car - a gas 2012 Chevy Cruze Eco 6MT. That car would never warm up if driven gently on really cold days, even at highway speed (there are lots of complaints from people even with the less efficient automatic equipped versions). On my short and easy commute I never got any appreciable heat out of it unless I left it in 5th (or sometimes 4th!) gear... burn more fuel, make more heat. I designed an elaborate plug-in heater system for that car consisting of the 200W OEM oil pan heater, a few stick-on pad heaters, a 1000W thermosyphon coolant heater and a 12V Prius water pump. With all that going on the engine would be just OK for commutes to work, but the physics were obvious; there just wasn't enough waste heat coming out of that little turbo 1.4 unless you deliberately drove it inefficiently.
So to wrap this up,
for what it is I'm seriously impressed with the economy of this car given its lack of apparent shortcomings. It's spacious and supremely comfortable year-round in a difficult climate, an AWD tank in the snow, powerful and quiet, handles well, and is impressively efficient (to me at least). Purchased used for less than 1/3 its original price with 88k kms it seems like a good value so far. Considering I put premium fuel in my Cruze it barely costs more to fuel this car with diesel.