Old 2-stroke Saabs had a freewheel to stop you running the engine without injecting fuel, as that would have run it dry of oil as well.
Now and then I’ve got it up to around 900 miles.
For some reason driving up to Preston from Cardiff returned the highest MPG I saw in the Passat, on one occasion 65mpg - and that's with the cruise set at 70. That gave me a range+distance figure of something like 1,050 miles.
Managed to get 55.9mpg indicated out of my 320d last night London to Poole with 5 up and fully loaded with clothes and food for the weekend, without using Eco mode.
I thought that was ok tbh.
That gave me a range+distance figure of something like 1,050 miles.
Mine's a Passat too. Must try harder.
Blimey, I'm definitely doing something wrong as I seem to be below 50mpg constantly in my 1.6hdi puggy Partner...right, I need to try much harder!
Blimey, I’m definitely doing something wrong as I seem to be below 50mpg constantly in my 1.6hdi puggy Partner…right, I need to try much harder!
Probably the shape of it. Vans aren't great.
My work Ford Connect, reasonably loaded I get 50mpg most of the time or 60mpg if I really try. That does mean running with the trucks, which I hate. So I'll do the speed limit and get around 50-53 mpg depending how much town work I do.
If there's a headwind, mpg suffers.
Eco mode is just horrible and makes a day behind the wheel very fatiguing, the 1.5? TD has precious little low down grunt as it is. It just feels like it's broken, unless it's empty of tools.
If every car was self driving and interconnected, then I suspect it could, as they could safely drive close enough to really make us of the slipstream effect.
As that isn’t the case, then I don’t think so, as a self driving vehicle likely wouldn’t be programmed to sit right up the arse of a lorry and take the risk that involved, like bored dad in his Volvo would.
They can indeed do this, it's known as Platooning. There have been some live-road trials already.
Must try harder.
Heh. Didn't do anything apart from set off at the right time to avoid traffic and put the cruise control on 70.
It wasn't that good on every trip, just that particular road. 60mpg was fairly common on a motorway trip. I'm happy to see 50 in the Merc though.
We deal with a few truck dealers at work. Some of the tech in modern trucks is very clever. The iDrive Volvo has autonomous cruise which also looks at the topographical map do it knows when it has an incline coming up and sets speed and revs according to the load. As it approaches the crest of the hill is does the same and coasts with regen down the other side. The operators are talking marginal gains but the total gains in a fleet of 100’s of trucks is mega bucks. Some drivers hate it as it removes them from the equation. Volvo dealer also has a full time trainer to teach drivers how to get the best out of the trucks economy.
Anecdotally I have noticed many more people driving well below the motorway speed limit lately, presumably to try and save fuel. I did smile at one I saw last week doing 55 mph or so, but with a double bike roof rack….with no bikes on it.
@jamesoz
I think the only Saabs with freewheel were the 93 and early 95 and 96, with a two-stroke engine.
Wikipedia page on Saab 93
I understand that the freewheel was to stop the engine seizing on the overrun (when you lifted you foot off the accelerator, but the car was still moving), like on a long downhill.
Being an early two-stroke, there was no separate oil lubrication system: it relied on the oil mixed in with the petrol for lubrication. If your foot was not on the accelerator, the engine wasn't taking in any petrol/oil mixture, so it wasn't getting any lubrication. Soon the oil film between moving parts would gradually get pushed out, and you would be left with metal rubbing on metal. That sort of thing tends to weld itself together, which is bad.
I'm sure someone who knows more about this will be along soon, but understand that best practice for two-stroke motorbike and scooter riders back in the day was: always pull the clutch in on the overrun. Also, always ride with two fingers over the clutch lever: if the engine seized and you were 'really' quick, you could pull the clutch in before the seized engine and back wheel caused a crash.
I believe that some commuter two-stroke scooters have a freewheel. Dimly remember something about some modern two-stroke engines have a separate oil pump, too. It doses the correct amount of oil into the petrol for two-stroke, and also pumps oil around the parts that need lubrication.
I drove a friend's Saab 96 with a freewheel. Could see how it might use less fuel with plenty of practice, but I didn't get beyond the stage of it feeling very strange.
Edit: just saw that this was covered by gofasterstripes. Oh well...
I learned it just the other day myself and your reply is much more insightful than mine
