A Driving Instructor's Blog

The blog gets hundreds of hits from people who have been taught to drive in a diesel, but who then find that they keep stalling now that they have bought a petrol car. When I pick up a new pupil I can often tell straight away if they have previously been taught in a diesel because many of them don’t set any gas before trying to move off. Even if they don’t stall every time, you can be sure they will stall right when you least want them to – at roundabouts or traffic lights when trying to move away briskly, for example.Forecourt fuel pumps

Anyone who has been specifically taught not to set gas when moving off normally has been taught wrong! They have simply been taught to drive a diesel, and only a diesel (and only their instructor’s diesel at that) – and as soon as they get in a petrol car they will stall it. In many cases it seems to boil down to some half-assed ideas certain instructors have about saving money on fuel (in theory, not setting gas saves them a penny or two a week).

Let’s get this straight: if someone has been taught not to set gas when moving off normally during lessons in a diesel, and the minute they get in a petrol car they can’t move it without stalling, then they have been taught wrong. It isn’t rocket science to work this out.

Face facts here. If you’re spending somewhere approaching £1,000 to learn to drive, do you think you’re getting good value for money if the moment you buy your own car you can’t drive it properly? If you keep stalling it, with all the dangers that could result? And all because your instructor didn’t teach you properly in order to save some imagined coppers?

Simply because they are learners, new drivers are often not precise enough with their clutch control, and what they’ve been taught to get away with in a diesel just backfires when they move to a petrol car. What makes the situation even worse is that many of these people don’t even know if the car they learnt to drive in was a petrol or diesel, so the instructors who teach this misleading method are obviously not doing their jobs properly on several levels. The unsuspecting new driver hasn’t got a clue how badly they’ve been taught until they get in their own car and discover they can’t move it.

I drove a diesel for many years. I’d driven petrol cars before that, and I taught in a petrol car for many years. Now I’m back to using a diesel. I have never driven my diesels any differently to the way I drove the petrol cars – and I never found a problem moving between the different types. There are four basic combinations when operating the pedals in any normal manual vehicle:

  • set the gas before the bite
  • set the gas at exactly the same time as the bite
  • set the gas after the bite
  • don’t set any gas at all

It’s fairly obvious that the learner needs the first option, certainly when learning to move off correctly. The second option is almost impossible for them to get right every time, and the third and fourth options (which the second one turns into if you get it wrong) can easily result in stalls. If your instructor is not teaching you to set the gas before finding the bite during normal driving, my advice would be to find another one quickly before you waste too much money. If you don’t you’ll join the ranks of those who start searching for the reason why they keep stalling as soon as they get their own car.

If you really know what you are doing, it’s up to you whether or not you set the gas or not. Most modern cars – petrol or diesel – will move off without it, but not very quickly. However, you need gas to move off briskly no matter what type of car you’re driving, and that includes automatics as well as diesels. Moving off briskly is particularly important if you’re dealing with a busy roundabout or a gap in traffic at a junction. Moving off slowly is dangerous, and on test it could easily end up with you failing. Even if you’ve passed your test, you’re going to really piss people off if you don’t get moving promptly, and you could end up in hospital (or worse) if you stall after entering a roundabout or busy junction.

Should you set the gas before finding the bite?

My advice is to set the gas first, then find the bite – whatever manual car you’re driving. If you don’t, you stand a good chance of stalling either now or in the future.

If you’re being taught in a diesel, bear in mind that you’ll almost certainly end up driving a petrol car at some point. You’re paying your instructor to teach you how to drive – not to play some half-assed game where he thinks it saves him money if you don’t touch the accelerator. It’s your lessons, your test, and your money, so work it out. There are some very poor instructors out there teaching very questionable stuff.

But do you HAVE to set the gas first?

There’s no rule that says you should, but if you don’t you’re likely to stall more often, particularly in a petrol car. If that keeps happening to you then I think the question answers itself, doesn’t it? If you found this blog because you keep stalling and still can’t work out the answer, let me say it for you: YES. SET GAS FIRST. Some cars simply won’t move without gas anyway – and these tend to be the older ones most new drivers will end up owning to start with. However, if you want to move slowly – during a manoeuvre or when edging out from behind an obstruction, for example – it is perfectly acceptable just to use the bite without any gas (if your car will handle it).

How many revs should I set before finding the bite?

It depends on the car you are driving. Don’t even think about trying to set it by numbers, otherwise you’ll get in a mess. Just set enough gas that the engine picks up slightly (i.e. the revving sound increases a little). How much gas depends on the slope you’re on – you can move off downhill without any gas at all, for example, whereas on a steep upward gradient you’ll have to set quite high revs compared with moving off on the level. It also depends on your car, because as I’ve already mentioned an older vehicle may well need more revs than a new one to avoid stalling in any given situation.

My instructor said to set 1,500 revs

Trying to set the gas by numbers creates a delay and distracts you, but setting it by ear (and feel) is much quicker. Trying to set 1,500 revs on the rev counter is very specific and you will begin to focus on adjusting it, whereas just listening (and feeling) for the engine pick up may well cover a range of as much as 1,000-1,800 revs (in a petrol car) on a level surface. As long as the car isn’t screaming at you – and you’ll know if you’ve got too much gas set – or stalling a lot then you have the correct amount of gas.

The chances are this idea boils down to your instructor trying to save money again. He or she doesn’t want you to rev to 1,600 because 1,500 is more economical. But that’s not the best way to learn to drive. Also note that the revs are often different between petrol and diesel cars, and the numbers here refer to petrol.

How can you explain how to set the gas to a pupil?

Everyone is different, and you’ve got to find the right words or exercises that click with any particular pupil.

Nine times out of ten, all it takes is for the instructor to ask the pupil to touch the gas pedal when he is explaining the pedals. They’ll often press too hard and the engine will rev loudly. Now get them to touch it as lightly as they can – and to hold their foot still – and ask them to listen to the noise the engine makes. That sound is what they should be aiming for.

You can liken the amount of pressure to trying to squeeze one drop of water out of a wet sponge (this works for the clutch, too, when finding the bite), one drop of juice out of a grape or orange and so on. Literally anything that makes sense to the pupil. It often helps to use something that you know they will relate to – playing computer games, football, a musical instrument, and so on.

Can I start my car without the biting point?

Check that you understand what the biting point is! It involves the clutch – and you do not want the biting point set when you start the car.

Perhaps you mean “should I set gas” when you start your car. The answer to that is “it depends”. Some cars don’t need it, and some – usually older ones – possibly will.

Can my car move away without setting gas?

I don’t know! Try it. Most newer cars can do it, petrol or diesel, but older ones – and especially ones which haven’t been serviced – may well stall.

Being able to move without gas is useful for low-speed manoeuvres and driving in slow-moving traffic, but not for normal moving off. If your car won’t do it then you’ll simply have to use gas. If you don’t, you’ll likely stall.

You don’t need gas on an instructor’s car

You do if you want to move away quickly! Instructors’ cars are no different to any other car other than for the fact they have an extra set of pedals fitted. The only reason you can often get away without setting gas on an instructor’s car is that it is usually quite new and well-maintained and is less susceptible to stalling. Virtually any new car will move off easily without gas – and this is especially true if it is a diesel vehicle with its higher torque. Using no gas is useful for slow speed manoeuvring, but it’s useless if you want to pull out on to a busy roundabout or junction and get away from other traffic.

As I’ve said elsewhere, if you’re being taught not to set gas when moving off normally, you’re being taught wrong. As soon as you get in a petrol car – and probably one that’s a few years older and more temperamental – you will end up stalling.

Should you only use the bite when reversing?

It depends on the situation. Since it is a little more difficult to steer accurately and safely when reversing compared with driving forwards, trying to do it faster is just asking for trouble. When you apply gas, it’s usually to go faster, so in this sense it often makes more sense to reverse with little or no gas so you can maintain control (if your car will let you).

Having said that, if you need to reverse in a straight line backwards, and you can be sure the road is clear behind you, and you can control the car, there is no rule that says you can’t use gas to go as fast as you need to.

One of my ex-pupils’ brother got in hot water recently with his dad. He tried to reverse out of their driveway at speed, and smashed the gate posts. He’d only recently passed his test, and to add to the irony their driveway is big enough to do a U-turn in, plus their gates are those electric ones which open and close automatically. The car was on loan from a grandparent and, along with the gates, sustained significant damage. It’s anyone’s guess at what was going on in his head to behave so foolishly.

Be sensible about trying to reverse with gas. If you aren’t very good at reversing, don’t use too much or try to go too fast. There is a growing number of cars these days with big vertical dents on the back where people have hit street lamps or road signs while reversing.

Why do new drivers stall?

Well, having been taught not to set the gas is obviously one reason, but stalling isn’t just down to that. I’ve written more about stalling in this article.

Can you stall a diesel?

Yes. People who have reached test standard only have problems when they switch to a petrol car because they have been taught the finer points of control incorrectly. Simply because they didn’t stall in the diesel they learnt in doesn’t mean diesels can’t be stalled – they can.

It’s worth noting that some modern cars are “semi-stallproof”. If you stall them, then immediately put the clutch down, they will automatically restart. They still stall, but there’s no fiddling with the key and restarting and moving off again is much quicker. You still need to make sure you know why you stalled, though – otherwise you’ll just do it again.

Why do I keep stalling my diesel car?

Usually, diesels are harder to stall than petrol cars. If you are stalling your diesel – and you are absolutely certain that if you got in a petrol car then you wouldn’t stall – my first reaction would be to suggest you have a fault and need to get it looked at in a garage.

As I have explained, a stall is when the engine is asked to do too much and stops. It usually happens because you bring the clutch up too quickly, don’t have enough gas set, or a combination of both these things. Stalling is more likely when you’re moving off uphill, and it gets even more likely as the gradient increases (i.e. the steeper the hill).

Are you sure you’re putting gas on? Your instructor’s car – if it was a diesel – was likely to be new and properly serviced, and you may well have been taught (incorrectly) not to set any gas. It isn’t just petrol cars that become more temperamental as they get older, and it may be you are trying to drive your instructor’s way in a car that just cannot handle it.

Why do petrol cars stall?

All manual cars can stall. Diesel engines are less prone to stalling because they usually have more torque – or “turning power” – which means they’re harder to stop. People who have been taught inappropriately (i.e. not taught to set gas, or allowed to be clumsy with the clutch) will have problems if they drive a petrol car simply because its lower torque makes it easier to stop the engine when it has load applied to it.

Should I brake before I put the clutch down?

It depends on how fast you’re going. If you’re slowing down from a cruising speed, then you should brake first – that way you get the advantage of “engine braking” (this is where the engine slows down as you take your foot off the gas, but since the clutch is still up it will also slow down the car). If you put the clutch down first, the car is effectively free-wheeling under its own momentum and the force of gravity, and that means the brakes have to work harder as there is no engine braking. On a downward slope, it will actually speed up in most cases if you put the clutch down first.

If you are slowing down below the lower speed for the gear you are in, then you will have to put the clutch down to either stop or change to a lower gear. If you brake too much for the gear you’re in, the car will start to rumble to let you know it is struggling. That rumble is a precursor to stalling, so you should change gear if it happens. Brake too much without depressing the clutch and you’ll stall.

I’m looking for advice on how to teach pupils in a diesel car

Teaching people in a diesel should be no different to teaching them in a petrol car. If you teach people to drive a diesel differently to how you’d teach them in a petrol car then you are not doing your job properly. They paid you to teach them so they can get a manual driving licence – not a diesel-specific one. If they don’t set gas first, the instant they get in a petrol car they will stall it. As I said at the start, the blog gets many hits from people having exactly this problem: they passed their tests in a diesel, and now find they cannot move away without stalling after buying a (usually quite old) petrol car.

Why do some instructors teach pupils using no gas in diesel cars?

Some of them have openly stated in the past that not revving the engine saves them money by using less fuel. I’ve read that on various forums over the years, and as with most things once word gets around, the practice becomes common even when the reason (however flaky it was in the first place) is long forgotten. The sum saved by not setting gas is minimal – it would probably amount to a few pounds a year on a mileage of around 30,000, even if it could be measured among all the other variables. A few hours driving into a strong headwind or sitting in a queue would cancel it out!

Another reason, I suspect, is that it is easier to teach someone when only one pedal is involved, so the method is perhaps also a bit of a cop out by those who can’t handle the challenge of teaching their pupils to drive properly.

Let me repeat the question I asked earlier: if you pass your test but then can’t move your own car off the driveway without stalling it because no one taught you to use the gas, have you received value for money? I think you can work that out for yourself.

(Visited 14,114 times, 3 visits today)
Share