Drive-By-Wire Throttle "Calibration" Procedures = Lore/Legend?

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There are these so called procedures floating about the interweb claiming that performing a rain dance with your ignition and electronic accelerator pedal in drive-by-wire throttle vehicles, achieves some sort of calibration or lining up of the stars between 1. The electronic accelerator pedal 2. The ECU and 3. the throttle plate position within the throttle body. It usually consists of keying on the ignition without cranking the motor and pressing the gas pedal and releasing then turn key off, Lather Rinse Repeat, three or four times. Since throttle-by-wire systems feature two sensors on the pedal assembly and also on the throttle body which cross check the voltage, I say any perceived results from doing these things is placebo effect. What do you think, Legend or Legit?
 
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Virtually a myth, or legend. I've never experienced any difference in the throttle action when the "rain dance" or nothing was done after disconnecting / reconnecting throttle body wiring. Having said that, my experience is limited to Fords and VW.
 

Astro14

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The ECM/TCM in the Mercedes W220 does "learn" the owner's driving style and adapt. It is roughly that process you describe to reset the adaptations. What works on a 14-19 year old German luxury car probably won't work on the majority of cars out there.
 
Most fly by wire vehicle do have a method to "calibrate" the throttle blade. VW's must have a TBA or throttle blade adjustment anytime the throttle body is removed or cleaned or the battery is disconnected. This can only be done with the proper scan tool. Most vehicle have a similar methods, so no it's not a "rain dance" and if not properly done the vehicle may set codes, and or have driveability issues. Reach manufacturer will have a process to correlate the actual pedal with the throttle body blade.
 
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My 2013 Bmw 750 gets a little laggy after long periods of slow city stop and go trafic. I turn on ignition, wot in 30 sec, ignition of and then let go of the pedal. Wait 2 minutes before drive. This helps but not sure what it does. Some say it resets the throthle body and some say it fools the car to believe it was driving in 30 sec with wot. The problem has to do with the adaptive throthle/gearbox somehow
 
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When I replaced the battery on a Sienna and a Forester, the only things I've done was KOEO deadhead for 30 seconds and then start the engine and let it idle to operating temp or the fans cycling to relearn the DBW throttle and idle strategies. I learned that from a Honda tech a while ago. On a Prius it was close to a non-DBW car and I let the DBW/idle learn passively. On a Matrix, when I had to disconnect the battery I did the deadhead but the car ran like crap until it stalled. I started it up again and it took about 30 minutes of idling and stalling for the DBW and idle relearn to happen.
 
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Had an 02 camry with early DBW that did not want to idle after the battery was disconnected-- like after I changed the clutch. Took it up to 55, coasted in gear, then dropped it to neutral, then slowly stopped. It at least idled after that.
 
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I also had an 02 Camry that wouldn't idle after disconnecting the battery - my solution was to clean the filthy throttle body with a toothbrush, so it could re-learn the idle more easily.
 
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Early Toyota's were TERRIBLE after battery disconnect. They just would not idle. Thankfully, that was figured out quickly. There's really no way to "calibrate" an ETB by turning a key on and off. Most vehicles will run a self-diagnostic every time the key is turned off. If you have the hood open and listen, you can hear it click and clack for a few seconds as it relearns it's closed position. That, and the APP/TP sensors 1 and 2 are continuously monitored for correlation, any hiccup and you'll get limp mode.
 
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my 99 outback , whne i disconnected the battery would have to relearn to idle even though it was a cable system TB. when i disconnected the battery , the ecm would lose its settings for the Idle air controller. i had to drive around for a while for it to relearn . got tired of this and got a obd plugin memory saver.
 
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Originally Posted by nthach
When I replaced the battery on a Sienna and a Forester, the only things I've done was KOEO deadhead for 30 seconds and then start the engine and let it idle to operating temp or the fans cycling to relearn the DBW throttle and idle strategies. I learned that from a Honda tech a while ago. On a Prius it was close to a non-DBW car and I let the DBW/idle learn passively. On a Matrix, when I had to disconnect the battery I did the deadhead but the car ran like crap until it stalled. I started it up again and it took about 30 minutes of idling and stalling for the DBW and idle relearn to happen.
What's KOEO mean, Key On Engine Off ?
 
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On my mother's Five Hundred, the drive by wire throttle body just straight out failed one day, and I got a remanned one and put it in. The procedure was just to disconnect the battery, try to drain some power with the brake pedal, and then let the car idle for 20 minutes/operating temp without touching the gas to relearn everything.
 
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I had to replace the throttle body on my XTerra and when I did, I had a check engine light and a very high idle until I successfully did the relearn process.
 
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Nissans have had throttle relearn processes for a while, they definitely exist, although they are not typically required unless something is touched and/or replaced.
 
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Athens, GA
On many Honda/Acura vehicles, holding the throttle to the floor and turning the ignition on for 30 seconds resets the PCM. Lots of people do that to reset the adaptive learning of the transmission and throttle. Makes the car feel more 'lively' so they say, right up until it relearns everything. I don't bother unless I have a legit reason I need to reset the PCM.
 
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