Question about RPM in Comfort Mode (and a bit concerned)

So I'm driving down a suburban road today at about 42-43 mph and need to pass a car; I eased my foot into the the accelerator and ... basically, nothing happened. Scary, sort of; almost felt like there was a malfunction, right in the middle of traffic - the X3 just didn't respond. Didn't have any passing power, until my brain processed it and I stepped down HARD on the pedal. That punched it down two gears and got the X3 moving.

That got me into testing mode.

I drove around and noticed something I hadn't before. In Comfort Mode, starting from a stop light and getting to about 55-60 mph, the X3 cycles through the gears and gets to about 2,000 rpm, and then kicks down (or is it up?) to about 1,500 rpm if constant speed is maintained for a little while or no pressure is applied to the pedal (coasting). If the X3 slows down to about 45 mph, the rpm reads 1,200-1,300. And there it languishes, with insufficient torque to do anything but cruise forward in a lane, until I definitively punch it into a lower gear. It feels like it's sitting in 8th gear when it should really be in 7th below some speed like 55 mph.

So then I tested in Sport Mode. Sport Mode seems to take it two gear lower. At the same 45 mph (coming down from 60), where Comfort Mode is 1,300 rpm, Sport Mode skips a gear that'd put it at 1,700 and goes right to 2,000-2,100.

Which raises two questions:

(1) Is it bad for an engine to run at such low rpm (1200 in Comfort Mode)? It does seem like it's huffing and puffing at that rpm, and certainly is not a comfortable (or safe) lack of power for any kind of traffic situation. That's almost idle!

(2) Is there anything that can be done to get the engine into the sweet spot of 1700 rpm and stay there at 40-50 mph? Seems like that's a range that neither Comfort nor Sport mode wants to stay in, but that's usually the best mix of fuel economy and torquiness.

Anyone else experienced concern about the low rpm in Comfort Mode at moderate, suburban driving speeds - say, between 35 and 50 mph?

tnx

It's trying to save you gas. If you need to get out of the way, floor it. Running at low RPM will not hurt anything.

Which engine, did you mention? I enjoy "manual" shifting at times.

this is for the 28i.

I'm aware that BMW does stuff on the X3 (and other models) to try to squeeze out another mpg or two for the CAFE ratings. Yes, it's trying to save gas. For the most part I applaud that effort. However, it's a bit deceptive - not an apples to apples comparison with other vehicles. Who knows, a Hummer or Escalade might get 21/28 mpg too if they ran at 1,200 rpm at 40 mph. I have a feeling it's like Stop/Start, something that has more to do with government reporting than taking care of the driver. It is not really safe, or comfortable, to lug around an X3 at 1,200 rpm in suburban, busy traffic at 40 mph.

I wish they had something in between Comfort and Sport mode - a Spomfort mode, where you get the Driving Miss Daisy throttle response and shift points of the first 3-4 gears for lugging the wife around, followed by a more normal maintenance of 1700 - 2000 rpm in gears 4 or 5 through 8 for safe, moderately powerful driving.

I had a 28i loaner car for a month while I waited for my 35i to be delivered. Felt the same way about the 28i...the 35i has sufficient torque across the whole rpm band to respond quickly in all gears. A turbo charger can only do so much to help when the displacement is so small.

The easiest thing to do is to throw it in DS mode when you are passing or simply drive the car in sport mode. You can also try reseting the adaptibe transmssion by following procedure:

1) hit start button once to turn on power (Don't start the engine)
2) then press the accelerator down to the floor for 30 sec
3) then hit start button once to turn off power
4) then remove foot from accelerator
5) then waite for 2 minutes
4) then start the engine like normal and try it out

This works for the F10, not sure about the X3, it needs to be repeated every so often to reset the learning curve. If you dont baby the car and drive it more agressively, the transmssion software will learn to shift at a higher rpm.

Hmm, I'm not sure I agree with the sentiment that it isn't safe. When I need to move quickly I floor the pedal (without pressing the kick-down button, which I think actually does more harm than good) and the transmission immediately shifts to get the RPM to the meat of the powerband, around 4k and I can move out of the way. On these modern transmissions the gear change happens almost instantaneously, and even though when I do it I get a bit more grunt from my 35i, the torque from your turbo should be in around the same place and should get you going well. The reason our vehicles can run at 1200 RPM at 40mph and a hummer can't is because we have a few extra gears to play around with.

When the transmission is so fast to respond, you might as well save the extra fuel. You'll just need to get used to the amounts of pressure required to make the transmission do what you want. I find when in doubt, to the floor but not past kick-down is perfect.

OP here.

Vortec - could I ask, what is a "kick down button"? The only thing I know of to force it into a lower gear is to step down on the pedal. Are you referring to doing it manually in DS mode?

tnx

Good question.

Next time you're in the driver's seat, before you turn the engine on play with the pedal. Push it all the way down, then push it harder. You'll feel an extra click when you apply that extra pressure and the pedal goes a little further. That's the kick-down detent, and it signals to the transmission that you really, really need to get moving and it drops as many gears as possible. The problem is these extra couple gear changes do take a little extra time, and with our turbo engines they do little to help because they're past the effectiveness of our turbos. Plus almost immediately after that extra gear down the transmission takes time to shift up at redline. Overall I find it's more effective in most situations to floor the pedal up until but without activating that extra button, but try it for yourself as your results may vary.

Originally Posted by Hardrada

So I'm driving down a suburban road today at about 42-43 mph and need to pass a car; I eased my foot into the the accelerator and ... basically, nothing happened. Scary, sort of; almost felt like there was a malfunction, right in the middle of traffic - the X3 just didn't respond. Didn't have any passing power, until my brain processed it and I stepped down HARD on the pedal. That punched it down two gears and got the X3 moving.

That got me into testing mode.

I drove around and noticed something I hadn't before. In Comfort Mode, starting from a stop light and getting to about 55-60 mph, the X3 cycles through the gears and gets to about 2,000 rpm, and then kicks down (or is it up?) to about 1,500 rpm if constant speed is maintained for a little while or no pressure is applied to the pedal (coasting). If the X3 slows down to about 45 mph, the rpm reads 1,200-1,300. And there it languishes, with insufficient torque to do anything but cruise forward in a lane, until I definitively punch it into a lower gear. It feels like it's sitting in 8th gear when it should really be in 7th below some speed like 55 mph.

So then I tested in Sport Mode. Sport Mode seems to take it two gear lower. At the same 45 mph (coming down from 60), where Comfort Mode is 1,300 rpm, Sport Mode skips a gear that'd put it at 1,700 and goes right to 2,000-2,100.

Which raises two questions:

(1) Is it bad for an engine to run at such low rpm (1200 in Comfort Mode)? It does seem like it's huffing and puffing at that rpm, and certainly is not a comfortable (or safe) lack of power for any kind of traffic situation. That's almost idle!

(2) Is there anything that can be done to get the engine into the sweet spot of 1700 rpm and stay there at 40-50 mph? Seems like that's a range that neither Comfort nor Sport mode wants to stay in, but that's usually the best mix of fuel economy and torquiness.

Anyone else experienced concern about the low rpm in Comfort Mode at moderate, suburban driving speeds - say, between 35 and 50 mph?

tnx

If you have exhausted all drive modes, and none suit your fancy, honestly you can do one of the two:

Switch brands and vehicle (X3>competition or X3>X5)

or

Just drive in the manual mode of the X3 or the DS mode if you dont like shifting. However do note, that you have an 8 speed transmission, and the only way to get you to get what your looking for is probably full manual, and staying in say a lower gear.

THis is the new efficient BMW

I run our X3 x28i in Sport and manual shift mode all the time. If I'm on extended highway drive I might move it over to drive and comfort mode. I'm used to the pull out our former 535i and running the X3 sorta mimics that.

"THis is the new efficient BMW"... brought to you buy your government's love affair with over-regulation.

Just drive in the manual mode of the X3 or the DS mode if you dont like shifting. However do note, that you have an 8 speed transmission, and the only way to get you to get what your looking for is probably full manual, and staying in say a lower gear.

THis is the new efficient BMW

This is where I've ended up. I never bothered with DS mode on other bmw's before, but tried it today and discovered it's pretty much what I was looking for: one gear lower so therefore higher RPM across the whole spectrum of road speeds, but with the relaxed throttle response of Comfort Mode rather than the over-punchy nature of the Sport Mode. And with the nice bonus of killing the Stop-Start madness. It suits me well. I quite like how you can just punch it in when you need it and then easily nudge out of it when there's no reason to have it engaged.

Can't wait for the eco-extremists to move on to their Next Big Thing so that cars can go back to being cars, not political projects on wheels.

Originally Posted by Hardrada

Can't wait for the eco-extremists to move on to their Next Big Thing so that cars can go back to being cars, not political projects on wheels.

I think those days are over.

7th and 8th gears are effectively overdrive gears. When you're cruising at a pretty stable speed it'll probably think you're just loafing along. I would try to pursue the logic reset procedure. Even in my Audi's 6sp automatic I find that the car "sleeps" when cruising in 6th gear... a quick toggle to Sport mode usually resolves that if I have to do a passing move