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Comment by jmclnx | Hacker News Reader

Someone I knew has a Rabbit Diesel. That was at the time diesel fuel was cheaper than Gas, plus he lived in a Cold Region of the US. He went every were with it, even a few cross country (US) trips. IIRC it lasted far longer then the Gas Fueled Autos of the period.

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Mom had one while I was growing up, and even then, I was horrified at the noise, vibration, and harshness compared to the gas equivalent model. The Rabbit Diesel is very loud, and in an unpleasant, clattering way.

It's amazing how far diesels have come. I have a Range Rover diesel, and even most car fans don't realize it's a diesel until I mention it.

Yeah certainly agree with you as well in regards to the advances in tech. I get really excited seeing (hearing) new BMW (and other) diesels just because they’re so rare, wasn’t aware Range Rover used any diesels! Some of the big changes it seems happened relatively recently in the 80/90s when turbos and direct injection became common place?

There was a window in late 90s/early 2000s in Europe where certain countries company car tax rules made it often more economical to run the diesel model of a lot of German cars and as a result Diesel sales took off for a while. This is why you saw the innovations like Common Rail Injection etc and large increases in refinement that became prevalent in a lot of diesel cars of this era. There was so much improvements in diesel tech in this decade because of this. There are some legendary diesel engines like BMWs 3.0 straight six M57 etc from this time - the great low down torque made this one of the best engines in BMW's range, period.

With the more recent European emission rules, and the massive "dieselgate" scandal of course, there is simply far less appetite for further diesel innovation nowadays and in the future. Pump availability at the gas station of Diesel itself is also now pretty poor in North America vs Europe too. VW/Audi also had a great reputation for refined Common Rail diesel engines in this period as well, ironic given dieselgate.

The common rail stuff got so refined Audi even offered convertible A4s with diesel for the first time, diesel cabrios were largely unthinkable before due to lack of engine refinement. Generally these engines were still noticeably diesel sounding at cold idle, but once up to temp after 5 minutes it got a lot harder to tell unless in the cabin looking at the low rev limit on the dials.

Is that what gives diesels their trademark rattley sound, the injectors?

Not an expert or a mechanic but in general find engines to be "more clicky" when low/lower on oil - had generally thought this to be the sound of the valves actuating. With less oil the sound is more pronounced. Maybe the "lower pitch" and the rest of the sound has to do with the high compression ratio (and exhaust or lack thereof). TDI engines can sound super clicky compared to larger truck engines

Pretty good discussion here as well (cool didn't even know there _was_ mechanics stackexchange): https://mechanics.stackexchange.com/questions/26513/whats-th...

Edit: would assume 4-cyl pistons need to actuate/fire ~twice as much as an 8-cyl engine at equivalent rpms? maybe that would explain smaller engines being more clicky idk

No.

While there is some noise from the injectors (in some gas-direct injection engines you can hear them as well, if you listen carefully) the sound you are hearing in an old diesel, that handful-of-marbles-in-blender-clatter, is due to the more abrupt combustion in a diesel engine in general (only air is compressed, and the fuel burns almost instantly on injection) and imprecise/poor timing of the old mechanical injection systems. Modern common-rail electronic-injected diesels are almost as quiet as gas engines.

I have a modern Golf diesel (2014) and love it[1]. I think they pipe artificial or modified engine noise into the car when you give it the beans.

Sounds awesome ...as long as you don't open the windows. If I do it still sounds OK but you can tell it's a diesel.

I've had it from new and it's still so good on fuel I guess I'll keep it till it dies. My record is 82mpg (UK gallons) on a motorway run. Nothing's ever gone wrong on it and it's cheap to service. It has all the features I need like Adaptive Cruise.

Not sure I'd replace it with an ID or whatever the new VW replacement is but there's something just right about the Golf design.

1. Luckily it's from just after the Diesel Gate affair.

I thought the dieselgate models were up to 2015?

https://www.caranddriver.com/news/a15339250/everything-you-n...

While the behaviour was terrible, my understanding is that the vehicles were better to drive during that era.

A well maintained diesel gets absolutely massive miles over its life, and it sounds like you’re on that path.

> My record is 82mph (UK gallons)

Do you mean ‘miles per gallon’? Either way, it’s impressive.

> I thought the dieselgate models were up to 2015?

Not sure when effected sales ended but I know my car didn't require a software upgrade as it was the next generation engine.

> Do you mean ‘miles per gallon’? Either way, it’s impressive.

Nice! Yes I did, now fixed thanks. Yep I was pleased with that. I did have to follow a lorry for about 100 miles to get that figure but I wasn't in a hurry. Going a bit steadier and slower makes so much difference.

My normal MPG in summer would be around 65MPGish.

(UK gallons are bigger than US gallons so it's not quite as impressive as you might think. I must switch over to metric for everything.)

I own a US Jetta 2011 TDI post-fix. I believe in the United States that ALL 2.0L Common Rail VW diesels sold in the US were affected[0] and (depending on owner’s discretion) either fixed at VWs expense, or bought-back and resold after the fix was applied. There are likely no pre-fix VW CR TDIs driving the roads in the United States today. The extended warranty was enough to incentivize even the most sovereign of citizens to take their vehicle in. Then in 2015 they stopped selling them altogether in the US. Jealous of the Euros…

Mine gets about 42 US MPG if I keep a light foot, which can be hard given how fun it is to drive. Usually works out to around 450mi a tank give or take (14 US Gallons) depending on how I feel on fill-up day about fiddling my thumbs to wait for the foam in the tank to go down to top it up to get it to “all the way filled.” I love it to death and will drive it until the DPF gets clogged, then delete and keep driving. Just bought a MK4 Jetta TDI as a beater to see if I can drive it to the moon once or twice. :) Cheers!

[0]:https://www.epa.gov/vw/learn-about-volkswagen-violations

> 82mpg (UK gallons)

Damn impressive!

That's 3.44 L/100 km for any confused Europeans :D

Thanks. Something I've noticed is that cars much improve after about 30,000 miles (48280km). I guess things like the cylinders get lapped by the pistons.

I want to own a more environmentally friendly car. Right now I think I'm best served by keeping my existing Golf for as long as possible and just trying to keep the mileage down (I live in the country not a town/city).

I drove a Rabbit Diesel back in the early '80s. It was not a luxury driving experience, but 48MPG highway! I didn't have much money and squeezing in a 700 mile round trip would let me visit my girlfriend over a weekend. Lots of miles in that car (mostly in the dark hours of the night, middle of nowhere, with Tangerine Dream blasting).

I doubt it would come close to passing modern safety standards, and I guess we saw how likely it would be for VW to make it clean enough for modern emissions… but it was an economical car to buy and operate. Here we are 40 engineering years later and all of the "New Small Cars With the Best Gas Mileage for 2022" have worse highway mileage than that 1980 Rabbit.

I drive the current BMW 3 series with a 150 PS Diesel engine and in summer I manage to get between 47 and 51 mpg at about 130 km/h (about 80 mph) on the highway. And I'm not even trying too hard to save gas. VWs current Diesel engines have the same mileage.

But you have 40+ engineering improvement on his VW. And the last 40 years have been revolutionary for engine performance.

In the end cars got heavier and their cross sections bigger. Killed all the would be fuel improvements

My dad had a mk2 diesel. He used less than 5l/100km and drove for 200000 km until he sold it with 350000km. As far as i remember he never had a serious issue. It wasn't a comfortable ride but very reliable.

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