I've just replaced my 91 BMW 320 16 valve manual with a 93 320 24 valve automatic transmission. This is my first automatic and I have immediately noticed both poorer performance at low speeds and overall much higher petrol consumption. Leaving aside the possibility of there being a fault with the new car, I wonder if I'm not driving the automatic correctly? Has anyone any tips to get the best economy/performance combination or can let me know about anywhere I can read up on this? Thanks
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In the traffic light derby, you sit with your left foot on the brake and your right covering the throttle. Then as soon as the lights go to red and amber (or 5 minutes after they have gone green if you live in the provinces) you just floor the right and lift the left at the same time. This makes your car even faster than company cars.
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Bad practice to sit with "Drive" engaged.
One, it heats up the oil in the torque converter.
Two, if you sneeze your foot comes off the brake and you're up the arse of the guy in front.
Three, if your reactions are so slow that you can't slip from neutral into "drive" as the lights change you shouldn't be on the road in the first place.
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Chas,
I'm not sure if Richard was joking, but don't sit at the traffic lights with your foot on the brake pedal if you've just done some heavy braking because the pads will be very hot and will cause a local hot area on your discs. This could cause your discs to warp and you would have "'judder". I believe that generally Autos have more disc problems because drivers hold them like this whilst stopping for short periods like at lights, does anybody else agree.
Pat
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I wouldn't have thought it was mainly automatic drivers who hold the car stationary in gear and not using the handbrake - most people do it, sometimes for quite long periods.
The traffic police around here have a favourite cautionary tale about a big diesel 4x4 which was stationary waiting to turn right in a protected area when it was shunted very gently from behind. The 4x4 driver's foot came off the clutch and because the car already had some right lock on, it went across the road in front of a fast moving lorry. Both occupants were killed. The car which did the shunting was completely unmarked.
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Well thanks everyone for the tongue in cheek replies and all the stuff about sitting at traffic lights, but I wonder if anyone has an answer to my original question? Perhaps there isn't one?
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So far as I know, automatics have always used more fuel than manuals although the technology changes rapidly and modern systems are different from older ones.
Although my experience is limited, I think that automatics demand a more relaxed driving style than other contributors to this thread might suggest.
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Autos have to use more fuel because the energy used to change gear AND engage/disengage cluches comes from the engine rather than the driver. As far as hot spotting the discs at traffic lights, I suppose if you drive at 100 mph between every traffic light it might be the case... I think autos wear out brakes faster simply because there is less enging braking. (There is none in first, unless you select "low" in some cars.) As far as leaving it in D at traffic lights, i don't think it does any more harm than sliding in and out of N. Auto boxes seem to pack up because the 1st gear clutch goes. It it's left in gear, this should save the clutch. It's cheaper to change the fluid once in a while. As far as sneezing goes, what about the other end? Incidentally, now that the police are ticketing people for drinking water at traffic lights etc, is blowing one's nose in a car an offence?
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