0 Members and 1 Guest are viewing this topic.
Just to bring this back to driving for economy...
I prefer to go down hills in 4Th or 5Th (like the feel of a little engine breaking and prefer not to ride the brakes any more than I have to..)
ParkingWhere possible try to park facing downhill, and in spaces where you don't have to reverse in or out
QuoteParkingWhere possible try to park facing downhill, and in spaces where you don't have to reverse in or outPark facing downhill in a car park, let go of your open door and it "falls" into the car next to you. Or worse still there's into yours.Park facing uphill and the doors at least fall closed.In a car park never park adjacent to a car facing down hill.
Slowing downRemember the fuel pump cut-off. If you don't have a scanguage this is not obvious, but then you are decelerating don't dip the clutch and coast, keep the car in gear because the ECU turns off the fuel pump.
You need to change down when this happens. It is a quirk of the diesel which improves a bit with more kilometres on the clock ...
Quote from: Dazzler on July 05, 2011, 12:41:14You need to change down when this happens. It is a quirk of the diesel which improves a bit with more kilometres on the clock ... So you think it is labouring.It's funny about the diesel this way, how the petrol does not labour as long as you don't push the throttle and expect it to do work, whilst the diesel even with no load/throttle may exhibit this sign.
You will find that you need to drive considering the lowest speed in each gear more than with a petrol. This means pretty much means keeping out of the 1000-1500 rev band in anything other than 1st and 2nd and not coasting to a stop in 4th lower than 1100 revs else the engine will attempt to maintain drive.
Although our cars are autos, in a manual I wont use neutral at all while moving especially down hill. This puts 100% of the breaking load on the brakes, allows the car's speed to increase, requiring more braking and heated brakes ...
I wish to deal with coasting in gear and the fuel, used as opposed to coasting in neutral. It is my experience by observing the fuel, used when coasting that it is better to coast in gear in the diesel vehicles we own. No not "better" but an alternative mode that is better in some circumstances.According to the Scangauge in the i30 CRDi and the real time fuel consumption readout in the ix35, when coasting their is 0 fuel being used by the vehicle, provided you foot is off the accelerator. Correct, I did say that.If this is correct, and I have no reason to doubt the readout I am seeng, coasting down hill in gear has the added advantage of engine breaking.Correct, but only an advantage if you wish to slow or maintain speed. Otherwise a disadvantage as I said before because you will waste momentum.I have driven this way in the i30 for just under 5 years, done 154 000 km and have not needed to replace the break pads, evidence that sensible engine breaking reduces the need for direct breaking and at he same time, helps to conserve fuel.A good result. Modern diesels with electronic fuel injection from common rail controlled by a myriad of sensors via an ECU can shut off fuel delivery when coasting and begin delivering fuel when required to keep the engine turning over.Correct.Those of you who know the SE freeway from the top of the range into Adelaide will realise that, if I am correct, almost no fuel is used with minimal need for breaking. Observation of the Scangauge on the way down shows that fuel usage remains at 0 for the majority of this journey of 9km.This is a good example of when coasting in gear is correct.This information (link included) confirms what I have discovered through personal observation.CoastingAlthough it used to be quite a common practice to save fuel, rolling downhill or approaching a junction with the car out of gear is inadvisable because the driver doesn't have full control of the vehicleI don't think a blanket statement can cover all situations.You lose the ability to suddenly accelerate out of tricky situations.So keep it in gear if it's tricky.You lose engine braking which risks brake fade on downhill stretches – overheated brakes require harder pedal pressures to stop the vehicle.That's the whole point misunderstood in this statement. The idea is to avoid engine braking when you don't need to maintain speed or slow down.With changes in vehicle fuel systems coasting won't save you fuel these days either.This is just wrong. You will use less fuel when coasting in gear but when balanced with the momentum loss you may use more fuel.Old car with a carburettor – take your foot off the accelerator pedal with the car in gear and fuel is still drawn through into the engine. Fuel savings could be made by coasting out of gear.Irrelevant here.Modern car with electronic engine management – fuel and ignition systems are effectively combined and controlled by one Electronic Control Unit (ECU). Take your foot off the accelerator and the ECU cuts the fuel supply to the injectors anyway so there's nothing to be gained by coasting.Again, presupposes the idle fuel used will be greater than that saved by maintaining momentum.Modern diesel engines also have the ability to shut off the fuel when you take your foot off the accelerator.http://www.theaa.com/motoring_advice/fuels-and-environment/drive-smart.htmlTis website gives great information about driving economically. I have quoted just a small part of the available advice and information.
My eyes! My eyes! Any chance of changing that blue to something a bit more eye friendly, pip?
I taught both of my girls not to do it when I was teaching them to drive.
Quote from: rustynutz on January 20, 2013, 02:18:57My eyes! My eyes! Any chance of changing that blue to something a bit more eye friendly, pip? Is that better Rusty? (Hope you don't mind Pip)
Quote from: db08 on January 20, 2013, 02:08:20I taught both of my girls not to do it when I was teaching them to drive.Likewise, I never tried to teach my son what is an advanced technique fraught with danger if the driver is unable to properly understand it, let alone get it right.And after 5 years of driving he has become a very capable driver. He changes gears exactly when and as required and even displays excellent understanding of traffic flow and reacts well ahead of time to situations - for which of course, I take credit. Still I see no need to make any changes. Economy is not a biggie for him.