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I suspect simply because they start engine braking a little time before you notice they are slowing. Your engine braking would then be insufficient because they have a head start in the deceleration process.
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Personlly I tend to have it the other way round - Car in front starts braking but I only need to release the throttle to slow down sufficantly (maybe it\'s because I tend to leave lots of space in front)
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I tend to agree with OP on this, probably for the same reason. I think I watch the brake lights of the car ahead but one,or more, and ease off without braking. Most people only watch the car immediately in front, and then have to slam on their own brakes because inevitably they are starting later.
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>>I think I watch the brake lights of the car ahead but one,or more, and ease off without braking. Most people only watch the car immediately in front, and then have to slam on their own brakes because inevitably they are starting later.
I agree with you CP. Although I once watched one of those driving programmes where they bring a psychologist on for their opinion on why people drive the way they do and he said that men tend to keep their eye on the car in front whereas women tend to look further ahead. Obviously not true in your case CP. Totally true of the male members of my family!
Fill what's empty, empty what's full and scratch where it itches!
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I agree with CP as well and find it annoying following these SUVs/MPVs/vans/lorries because I can't see thru their windscreen easily
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You'd love following the Synergie with the sunblinds down or with a full load wouldn't you? And I guess caravans make you apopleptic.
May I politely suggest following from a greater distance and varying your position on the road to see past what you can't see through?
Hawkeye
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Stranger in a strange land
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That's what I meant. You have to be pretty close to see the next car's brake lights through the windscreen of the one in front.
A similar effect happens when a stationary queue of traffic starts to move. Half the queue start to edge forward as soon as the one at the front moves, the rest (obviously the men, I now learn!) stubbornly wait until the car in front has already moved, and then do a sudden acceleration in their panic not to be left behind.
I coast (see alternative thread) up gently behind and usually the queue has started again by the time I get there.
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Could it be that the car in front is slowing down with his gears?
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OK, of those who don't need to brake how many are driving diesels?
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I am but diesels also have heavier flywheels and components so engine inertia comes into effect more so than petrol engined cars.
I was quite surprised when I drove my first diesel, I had anticipated far greater engine braking.
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When I had a new Zetec engined Fiesta in 1996 I was surprised by the non existent engine braking on the overrun. I made a few enquiries and was told that this was the management system doing its best to be economical. I also found a driving instructor who had the same car and found it was unnerving him and his pupils who had become accustomed to some engine braking. He had his car remapped by Ford to overcome the problem.
There were stories at that time that this resulted in VERY heavy pad wear in some cars such that service interval was too short to spot pads to metal! If this was the case Ford may have changed the mapping for all similar models.
Maybe the same design engineer just moved jobs to work on 99 Foci?
pmh (was peter)
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Might that explain some squeaks from the brakes of my new Fiesta, and what I think *might* be a decrease in braking performance. All of this just before the 12,500 mile first service...
Blue
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When I had a new Zetec engined Fiesta in 1996 I was surprised by the non existent engine braking on the overrun. I made a few enquiries and was told that this was the management system doing its best to be economical. I also found a driving instructor who had the same car and found it was unnerving him and his pupils who had become accustomed to some engine braking. He had his car remapped by Ford to overcome the problem.
I think my old N-reg Mondeo V6 must have had the same system- take your foot off, and it was only 1-2 secs later that you started slowing down. And it wasn't a particularly smooth transition, so if you put your foot back on just after it happened, it got a bit jerky.
Nice car though- no alloys/spoilers etc. so a bit of a q-car.
John
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I had a V6 mondeo too and when I asked about the over-run on accelerator lift-off I was told that it was to prevent jerky progress in traffic. Seemed like a cop-out to me but there was definitely a delay programmed in to the engine management system.
Otherwise it was a great car, but got too expensive to repair at 130k miles.
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I have had my S reg Focus 1.6 for over 3 years, and engine braking has always been almost non-existent. Going down a slight incline in a high gear, I always have to use the brakes at lot more than traffic in front, and it is nothing to do with following too close etc. This is the first car of mine that I have found this to be a problem, so don't think it is down to my driving.
Pete Mansell
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*Could* this even be due to the person in front not being in top gear, so having more engine braking?
My grandmother never used 5th gear once she got a car which had one - she'd only ever had 4 gears before and was quite happy to stick with just those, no matter how high the revs in 4th went!
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*Could* this even be due to the person in front not being in top gear, so having more engine braking?
I don't think so. It happens too often for that.
--
L'escargot by name, but not by nature.
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I have had my S reg Focus 1.6 for over 3 years, and engine braking has always been almost non-existent. Going down a slight incline in a high gear, I always have to use the brakes at lot more than traffic in front, and it is nothing to do with following too close etc. This is the first car of mine that I have found this to be a problem, so don't think it is down to my driving. Pete Mansell
Thanks Pete. That's precisely what I wanted to say, but at the time I didn't know how to put things. Your experiences mirror mine exactly. It's the first car I've had this problem with as well, so I don't think it has anything to do with my driving style either.
--
L'escargot by name, but not by nature.
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Lack of engine braking equates to economy??
I'm missing something fundamental here - engine management controls ignition/injection so no fuel at all on overun should equate to max engine braking (without changing down)- anything else would suggest that fuel is still being injected.
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Isn't it for emissions, rather than economy?
My dad's '87 Corolla had a carb that held onto revs for a second or two after you lifted right off. Seem to remember reading somewhere it was for improving emissions performance.
Meant you had to adapt your style though, as unlike earlier cars it wouldn't lose revs between changing up gears.
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Where I live it's brakes only. Leave more than a car's space between you and the guy in front and in a second someone will be in there (no indicators, don't expect any, never give the game away as to what you're doing)....Filipino machismo won't let him do anything less, especially if he sees I'm a forrinjer. Women are not so much of a problem, they crawl along in the fast lane primping in the mirror or texting on their cellphone.....
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What about the differences between automatic and manual gearboxes...modern electronically controlled automatic gearboxes have almost non-existent engine braking ability compared to the older hydralic automatics or manual gearboxes.
Ian L.
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Regardless of engine management system, lower gear means more engine braking (because the braking effort stems from the friction + compression effort involved in turning the engine; so more revs per distance travelled means more braking).
And sensible modern automatics do take this into account by selecting a lower gear when speed is increasing while foot is off accelerator.
It is amazing how few people will change down when going downhill. I often pass through Lamberhurst (on the A21) which is in a deep valley, and has a 30 limit through the village. It would seem everybody stays in 4th, or perhaps even 5th, thus having to keep braking in order to stay below 40! Whereas shifting down to 3rd keeps me and the old Golf gently plodding downhill, without brake pad wear. And then we're in the right gear for overtaking on the uphill at the other end of the village, after the end of the speed limit!
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Owned an 800cc BMW twin ,an R80/7, went for a test ride on a K75, 3 cylinder 750cc, and was pre-warned about the much greater engine braking.
Now gone to an 1150cc twin and the engine braking is even better.I guess compresion ratio , valve timing and gearing all make a difference.
My Passat diesel seems to gain on cars in front down the long trans-pennine hills. It is not especially highly geared , something like 30 mph/1000 rpm. If I do drop to 4th gear then the engine braking becomes more effective as you'd expect.
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"Whereas shifting down to 3rd keeps me and the old Golf gently plodding downhill, without brake pad wear."
Pads & disks cost a lot less than transmission parts though.
I'm not sure that engine braking is good practice. Wouldn't it increase wear on the whole transmission system? Not bad slowing on a motorway, but perhaps not good on a long downhill section?
I'd say it's a case of being in the correct gear for the situation, so at, for example, 30, that will most likely be 3rd in my car, and at 40, 4th. If the car is tending to 'run away' down a hill, I'll control it with braking.
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I find exactly the same problem as L'escargot. I hang back, say on a downhill, because I know some folks are nervous about going fast. But I catch 'em up. I slow and match my speed to theirs. And then I still catch them up!
(Not to be confused with 'Ooh, there's a suggestion of a little bend; dab on brakes needed.)
I put it down to others' cautious use of lower gears. This is bad news. One, changing down means wearr on clutch and transmission: brakes are cheaper. Two, and worse, it means brake dust on my sparkling alloys.
Once I'm moving, I hate slowing down unless I have to; it makes driving far more enjoyable and I keep my wheels clean. Simple.
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One distinct advantage of LHD cars in the UK is that it's easier to see three or four cars ahead of the one in front. This is especially true on motorways where everyone else tends to move over to the right, leaving a clear line of sight down the inside.
When I'm using the Chevy I often find that I'm slowing/braking two or three seconds before the driver in front reacts.
It's a bit awkward getting in and out of barrier-controlled carparks though!
Kevin...
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One distinct advantage of LHD cars in the UK is that it's easier to see three or four cars ahead of the one in front.
Yes, true on motorways, but how does that work on single carriageway roads?
For example when i drive in europe, in my own car, i am on the 'wrong' side to be able to see ahead for overtaking etc as to wander out for a little look ahead involves using almost all of the other side of the road!
Same problem with LHD in the UK surely
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Yes, true on motorways, but how does that work on single carriageway roads? For example when i drive in europe, in my own car, i am on the 'wrong' side to be able to see ahead for overtaking etc as to wander out for a little look ahead involves using almost all of the other side of the road! Same problem with LHD in the UK surely
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Funnily enough single carriageways aren't really a problem either. Bends in the road mean that you can always see down one side or the other and if you can't see past on the straights you're too close. Often though it's not even worth overtaking on single carriageways, you only get to the next obstruction quicker.
The only real problem I've encountered was an artic parked (illegaly) on a gentle left-hand bend with a tall hedge down the LHS. I couldn't see down the inside of him because of the hedge so I was totally blind. Luckily I've only come across this situation once and I had my wife in the passenger seat who could call the shots. Even RHD vehicles were having problems with this one.
Kevin...
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Pads & disks cost a lot less than transmission parts though. I'm not sure that engine braking is good practice. Wouldn't it increase wear on the whole transmission system? Not bad slowing on a motorway, but perhaps not good on a long downhill section?
Except that transmission parts don't fade.
Try the A404 into High Wycombe (from either direction) - a very long steep downhill stretch. Brake all the way down that every day and I wouldn't like to guess how long the pads will last. Alternatively, put the car in second at the top and roll down at the 30 limit and the car will happily sit at 3000 rpm or so without any throttle applied. Then, at the bottom, you have nice fresh brake pads to bring you to a halt at the junction. If anything happens on the descent, you still have the full range of control over the car.
I don't expect that 3000 rpm will be a problem for a modern transmission. There are also a plethora of signs warning of a steep hill, select a low gear, escape lane ahead, and a brand new rumble strip on the southbound approach, so it strikes me that there have been a number of accidents involving people who relied on their brakes.
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Patently, by coincidence I live near Henley so know the hills you mention into High Wycombe and use them both, though not frequently. I would normally stay in 4th to the 30 restriction, then use 3rd and control my decent with the brakes. Never found it to be a problem, and I haven't needed the escape lane yet! I use 3rd in virtually all 30 limits by the way, hill or flat.
You have eveidence to back up the claim that all the accidents where due to brake failure? The last one I read about I seem to remember being caused by the engine cutting out, removing braking assistance, and the elderly driver rolled into the gravel trap more in panic than anything else, being unused to unassisted brakes. I don't read the Wycombe paper so perhaps don't see all the reports.
I'm not an engineer so don't know if there will be damage, but I am concerned about the forces on the transmission coming from the 'wrong end' so to speak.
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GOG - I find that in 3rd the car tends to run up to about 35-40 so prefer 2nd for the 30 sections. Every car has its own ratios, though, so in a different car the same approach might dictate a different gear. I also tend to stay in 3rd in 30 limits so that I am less likely to allow my speed to drift upwards.
I know that one accident involved a 7.5 tonne lorry whose brakes failed, with the predictable results.
My point about having control of the car (btw) is that if you are descending at 30 or 40 then there is still adequate speed for a nasty bump if someone changes lane right in front of you, as they are wont to do on the northbound descent given the junction at the bottom. If you are holding 30 but using 75% of your braking power then you don't have a lot of scope for action. If you are in gear but pressing neither pedal then you have 100% braking effort available.
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I see what you're saying p - keeping a foot on the pedal all the way down would really cause problems. I apply and release every few seconds to keep the speed under the limit while not overheating the brakes.
You have picked the perfect example here as both hills are particularly nasty. :-)
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Hmmm. Fair enough as regards your car, but surely your speed then oscillates. Might that not cause problems behind you?
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