My 2008 550i is developing a lag in throttle response that is starting to get annoying. On my car, throttle response lags behind the inputs from my right foot, and is non-linear once the throttle begins to respond. Not unsafe or anything like that - but very noticeable and very annoying. Has anyone else experienced this issue with their drive-by-wire throttle? Any luck getting the dealer network to respond / fix this? Are there any service bulletins that address this that I could direct my dealer to? Any thoughts would be greatly appreciated. Best, John
Which transmission do you have? If you have the automatic, does the response get better when in "Sport" mode? Does the lag happen at higher engine speed eg when already at ~3500 RPM and then stepping on the gas?
Thanks for the reply. Yes, I have the tiptronic transmission. No, the throttle response does not improve when in "sport" mode. The lag is present at all rpms, but most noticable at normal driving speeds - 2000 - 3000 rpm. As I mentioned, once the throttle begins to respond, the resulting increase in rpm is not linear. Once the rpms begin to increase, they increase at a greater rate then called for by the input from my right foot. It's a strange sensation indeed. John
Interesting... I find that both the shift algorythm and the throttle response improve dramatically when in the 'sport' mode. Might be worth a trip to the dealer to see if any engine-mapping is off. Don
Same engine... It appears you and I have the same engine (the N62N) in our cars (mine is a 650i) & I assume the same motor management soft/hard ware. I too have noticed a substantial lag in pushing the right foot down & feeling the seat push me in the back- especially at ~40 MPH in traffic. I attribute this to the over-gearing used in an effort to get reasonable gas milage and an engine with relatively poor low end torque. It gets a lot better while in Sport which changes the gear selection, but I don't know if the pedal-throttle ratios are changed. I have heard several others comment on this underwhelming pedal response & attribute it to the drive-by-wire. I'm thinkin' it is the nature of the beast. How long have you had your 550? & how many miles on the car? Any fault codes found on your OBD eval?
Don't blame drive by wire throttle since manual transmission cars do not exhibit this behavior. Most every auto transmission BMW I've had to drive in the past 5+ years or so (loaners and test drives) exhibits this type of behavior, sometimes to a lesser degree but still annoying. Even a test drive in an Alpina B7 yielded a disappointing outcome, and I later read a review in C&D about the B7 where they complained about the same thing. I've been told different things by different people with some saying it is related to maximizing fuel economy on the mandated test cycles while others say it is related to minimizing emissions on said cycles. Whatever the reason, the last loaner I had when my M5 was in the shop (2010 328i) had simply awful tip-in and 0-1/4 range throttle behavior. It had a LOT of "push a bit, nothing, push a bit more, nothing, push a tiny bit more, then zoooommmm, now quickly take away some throttle" type of behavior. It drove me crazy, and I can't see how people put up with these auto transmission related throttle/tranny programming designs. I always ask for a manual transmission loaner (they don't have any), and get the same laugh every time.
I just bought an 03 540i sport auto with the same issue. I learned that the Dinan software will take care of the issue. There are no Dinan authorized dealerships near me, so I sent my DME out to Dinan to have the software loaded. I should have it back this week. The software makes the throttle linear just like a manual trans car or the old cable actuated cars. I don't think you will find any solution from BMW, you will have to go to the aftermarket.
Thanks, you've described the symptoms exactly. This exactly what my car is doing ! Sure, the transmisssion upshifts and downshifts constantly, but I've grown accumstomed to that and can time my brake / throttle inputs to coincide with gear changes - it's acutually fun - when the throttle gets past the lag and engages. Does the aftermarket software, either Dinan or Sprint Booster fully eliminate this behavior? I sure miss throttle cables..... Best, john
delayed trottle response My 2007 530i CPO has the same thing. When we purchased the car last spring, I thought the transmission was slipping when starting from a dead stop. The dealer checked it out, and said nothing was wrong. I 'm getting used to it, but it would be nice to have a better response without using the sport shift mode. On the positive side, it will be helpful starting from a slippery intersection in the winter time. fmanke
Here is an example of what I'm referring to when stating that "all" BMWs I've driven in recent years with auto transmissions have had this stupid problem. Fortunately a manual is available where the problem is non-existent (well, at least on everything but the 7 series). Note that this review is referring to the F10 535i and the F01 7-series lest someone think BMW has "fixed" this poor behavior in the latest models. See 10th paragraph:
Where's a torque curve? "...lest someone think BMW has "fixed" this poor behavior in the latest models." That lag describes the action in my 2010 650i (build date 4/09). I am still not convinced this is not the fault of a weak low-end torque curve of the engine. I have yet to find an actual torque curve for this motor. The BMW sport mode supposedly changes the tranny shift points (and what else?). My Saab sport mode changes only the ratio between the gas pedal and the throttle. That solution seems to work much better, if anything producing a "jumpy" launch across the intersection.
Go drive a 6spd manual version of the 650i, and you'll see that it has nothing to do with the low end torque curve of the engine (which is substantial btw!). Regards,
Well guys I just got my DME back from Dinan. Got it installed in my car last night and went for a quick drive. It is like night and day!!! Instant power is all I can say. Laid down two very nice black strips in front of my house!! How else do you advertise that a motorhead lives here? I am very happy with the change in throttle response. For slow starts you to have to ease into the throttle, but that is how you would on any car. So for those who don't like the lag and are okay with a sensitive throttle I would highly recommend Dinan's software. Added bonus is no top speed limiter, adds a few horses, ups the redline a bit, 100rpms on my car.
Will this affect my new car warranty? Did you get the variable boost (via the dash dial) unit? I still would like to see a torque curve. It seems to be top secret.
I don't know what you mean by variable boost? My car does not have turbos. I have an 03 540i sport. Dinan offers different software levels depending on what other hardware you put on the engine, throttle body, intake, exhaust, etc. I just went with level 1 because the only thing I really cared about was the throttle issue. 300hp is already enough for me. So for me it was not really about adding power. As I mentioned, the car is much more responsive now and I am very happy with the change.
]I don't know what you mean by variable boost? My car does not have turbos. I have an 03 540i sport. You're right, I chose the wrong term for your product. I had followed someones link about this: ----------------------- <http://www.sprintbooster.com/> SPRINT BOOSTER 'SELECTABLE PROGRAMMING' IS NOW AVAILABLE !!! The new generation of Sprint Booster debuted at SEMA SHOW 2009 winning one of the most important awards in aftermarket industry , the ‘SEMA BEST NEW PERFORMANCE-STREET PRODUCT 2010' award among 1400 new products. -------------------------- It too is a modification of the pedal- response curve, but has a dash mounted switch to moderate the degree of enhancement. I assume the Dinan solution is one setting. Again, any word on warranty issues? (even though your 03 is out of time)
The Dinan product is one setting, at least for now. Dinan is blessed by BMW just like Alpina. So no warranty issues. In fact you can get all of Dinan's products installed at some BMW dealerships. Go here to see if there is one near you. http://www.dinancars.com/bmw/dinan-service-centers
