Drive-by-wire Throttles

....never have given it a 2nd thought apart from the fact you can't heel 'n' toe due to the "safety" lockout.
 
One nice thing about DBW is cold starts, the ECU keeps the RPM right at the Normal RPM, no high idle. It took me a few weeks to even notice but my BMW idles at the same RPM at 5F as it does at 95F.



It does take some getting used to though, its not as linear as the old technology. I am dreading the next model of airplane I will be teaching as its entire flight control system is by wire, no mechanical backups at all. Thats a lot of faith.
 
The only problem Ive found out is that if there is a malfunction, The engine will disengage from the tranny. The reason I know this is that my wifes 02 Envoy had this and it was defective. I had to clear the computer to engage it in gear to move it. Other wise its just like being in neutral. Its not difficult to replace if it goes bad either.
 
From all accounts it would seem to me that regardless of manufacturer, you are involved in chance. ie the chance of getting a good well setup system, or a not so good laggy setup system ... which begs the question can this be fixed? In an attempt to answer my own question I would hazard a guess as yes it can, since DBW is computer controlled, one assumes that the software can be re-callibrated. I feel a visit to my dealer is on the cards :)



Oops apologies to the thread starter I am not sure we are addressing the issue specifically :/ It is an interesting thread though ? :)
 
AXE what year is your BMW? there is a retrofit for the DBW problem on 2001-and later cars, had I read your entire first post I would have addressed this earlier.



Search on Bimmerfest.com and you will find a ton of info on the retrofit. Sorry for the delay in answering your question. At least your problem has a fix....
 
Axe said:
.. you are involved in chance. ie the chance of getting a good well setup system, or a not so good laggy setup system ... which begs the question can this be fixed? In an attempt to answer my own question I would hazard a guess as yes it can..
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Not on the Audis. They reprogrammed each of my problematic ones, with results ranging from so-so (the S8) to "no different" (the A6 4.2). Word is that with the Audis, if you get a bad one you're simply SOL with regard to getting it fixed. Consider that they bought back my A6 despite its having 12K miles on it...good thing Stoddard Imports values our business.



Accumulatorette and I test drove a number of Audis and Porsches there last Friday. Interesting to experience the variations in DBW. Not *one* vehicle with both DBW and an automatic had perfect throttle response. Left us more convinced than ever that *we* prefer the older technology :(
 
Axe said:
Oops apologies to the thread starter I am not sure we are addressing the issue specifically :/ It is an interesting thread though ? :)
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Yes, it's interesting...but still waiting to hear from someone with a DBW GM 3800.



Accumlator--hard to believe that Audi can't fix these--if the software cal is ok, and some of them work, then it must be sensor variation, which they could at least try to fix by swapping out sensors. I'm surprised that there isn't that much Teutonic precision to that part of the car, although honestly I have had a completely unrelated work experience with a piece of German hardware that flabbergasted me with the "calibration" procedure, or lack thereof.
 
Accumulator- Lexus cars are the same way, nothing can be done if you get a bad one.



You can learn to compensate for it though, but I'm always stricken by how smooth a traditionally cabled throttle is when I drive one. You shouldn't go from a Lexus to an Explorer and go "oooh" when you apply the throttle because its so much smoother than what you're sued to.
 
GoodnClean said:
Accumulator- Lexus cars are the same way, nothing can be done if you get a bad one.



You can learn to compensate for it though, but I'm always stricken by how smooth a traditionally cabled throttle is when I drive one. You shouldn't go from a Lexus to an Explorer and go "oooh" when you apply the throttle because its so much smoother than what you're sued to.
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Heheh my car's throttle is smoother than yours. :D
 
Whenever I get into one of parents' or sisters' cars, I get yelled at for being too heavy on the gas. When you're used to a slight delay in throttle response, it is hard to instantly adjust to a cabled throttle. What is even worse is when you're driving a car with a cabled throttle and the transmission downshifts with the slightest increase in throttle. Good ol' days.



Then again, I still can't complain about DBW too much. I am really fond of the safety systems that can be better implemented by having DBW.
 
I've never felt this in the DBW hondas. Unless I just wasn't paying attention. But I've driven the new RL and it had an annoyingly touchy thottle.



And the assortment of other Acuras, although now that I think about it, the MDX had a weird throttle--kind of like a thermostat. Gosh I hate that car...but that's not the subject...
 
Regarding the initial inquiry, IMO if the GM you're thinking about had as many problems of this nature you'd have heard about them. With all the info available these days, stuff like that doesn't stay secret for long. Just look at this thread, both Audis and Lexus have been exposed as having unfixable BDW issues. If there were problems with the GM system, the various GM boards would have something on it.



Setec Astronomy said:
Accumlator--hard to believe that Audi can't fix these--if the software cal is ok, and some of them work, then it must be sensor variation, which they could at least try to fix by swapping out sensors..
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Astounded me too. They changed a myriad of parts but never got that A6 to work right. They changed a lot of stuff on the S8 too, but every now and then it still acts up (totally random). I just figure I'm lucky that it's better than my buddy's S8, his is a lot worse than mine. People in the Quattro Club have had enough similar experiences that at least I know it's not too unusual. Never heard of anybody who ever had it get fixed, but I've heard of plenty of people who just dumped the cars over it. Pretty awful problem.



Originally posted by GoodNClean

You can learn to compensate for it though...
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If it would just be consistent I wouldn't mind nearly as much...the scary thing is you never know when it's gonna respond and when it won't, so there's no way to compensate :( With the Cayenne we test-drove, yeah, you just had to learn how it behaves and then you were fine.
 
FalconGuy said:
AXE what year is your BMW? there is a retrofit for the DBW problem on 2001-and later cars, had I read your entire first post I would have addressed this earlier.



Search on Bimmerfest.com and you will find a ton of info on the retrofit. Sorry for the delay in answering your question. At least your problem has a fix....
Click to expand...



Oh I gotta go find this, I can't figure out how to search on bimmerfest ... my car is 2001 thanks for the tip will try again later. :)
 
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