gas pedal "overtravel"?

Brownd3max

Member
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2016 CX-5 Grand Touring
Maybe a silly question, but my recently acquired '16 GT fwd gas pedal has a definite "detent" resistance about 3/4 down the travel, and will go beyond that to the floor with more foot pressure. Is this normal? If so, what exactly takes place in that last inch of travel? Just a trans. kickdown? TIA!
 
Yes. Just kick down. On some cars with manual transmission, there is a detent to assist eco driving. I guess it would do the same.
 
Maybe a silly question, but my recently acquired '16 GT fwd gas pedal has a definite "detent" resistance about 3/4 down the travel, and will go beyond that to the floor with more foot pressure. Is this normal? If so, what exactly takes place in that last inch of travel? Just a trans. kickdown? TIA!

From the manual:

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Thanks guys- that manual quote posted by "exeler8ing" sure is a wordy explanation for a simple thing. LOL! Much appreciated though!
 
From what I understand it’s not only how far you push on the throttle pedal but how fast as well.

The computers are fine tuning every aspect and sometimes the result is not quite what you might expect or had previously experienced with previous vehicles. Every vehicle has its own quirks and nuances which we all get used to. (Most of us that is)
 
Anchorman, would you happen to have access to any documentation regarding the throttle?
 
Thanks, that was illuminating.
Anything regarding the logic?
 
I mean the way the ECU or ECM or whatever interprets the movement of the accelerator pedal. :)
 
It’s pretty much in that graph where the APP (accelerator pedal position) sensor or potentiometer just requests power anywhere from idle to full power. The pedal provides the feel with increasing resistance and the detent for the kickdown isn’t really connected to anything. In other words, if the spring in the detent broke, it would still kickdown at that level of power. What happens at the other end will be determined by the engine management ecu and the throttle body and the fuel injectors all in combination. They all have their own pdf which I will find for you but you’ll have to wait while I get chance ;-)
 
They all have their own pdf which I will find for you but you’ll have to wait while I get chance ;-)
No hurry, appreciate all of your contributions.

I was wondering if [and if so, how] the ECU reacts to the speed of pedal travel as well, as mentioned by Puyapim. I've heard rumors of that before.
 
This pdf is for the 2.0G but its virtually the same. You can see that the accelerator pedal is the only thing the driver consciously inputs to make the whole thing chooch. The PCM takes many inputs in determining just how it will convert that pedal request and instructing the outputs (making the engine respond as requested). I think this is what you were asking for but if not, let me know
 
I was wondering if [and if so, how] the ECU reacts to the speed of pedal travel as well, as mentioned by Puyapim. I've heard rumors of that before.

Not really. The PCM controls engine knock and flat spots under rapid acceleration and also heavy lurching at low speeds when the accelerator is released suddenly. I think you might be getting mixed up with rapid brake pedal inputs which will be interpreted as emergency braking and lower pedal input pressure. Try it on a quiet road at 30-40 mph. Hit the brake pedal as quick as you can and it will stand on its nose without the usual pedal force.
 
Thanks for that! It doesn't address my question, but certainly showcases the complexity.

Do you see anything titled "drive-by-wire control" or something similar? I think that might apply.
 
Not really. The PCM controls engine knock and flat spots under rapid acceleration and also heavy lurching at low speeds when the accelerator is released suddenly. I think you might be getting mixed up with rapid brake pedal inputs which will be interpreted as emergency braking and lower pedal input pressure. Try it on a quiet road at 30-40 mph. Hit the brake pedal as quick as you can and it will stand on its nose without the usual pedal force.

Not thinking about braking, just acceleration. For instance, will the engine respond to full throttle differently [more quickly] if the pedal is rapidly depressed rather than gently but quickly [squeezed?]. Stomped rather than stepped on perhaps.

Maybe I just need to do more seat of the pants experimentation.
 
Funny how this detent "feel" in the go-pedal reminds me of my '69 Chevelle SS I sold last year- It had a built454 with an 850cfm double-pumper with mechanical secondaries. When you hit that resistance in that gas pedal, then mashed it, the secondaries snapped open, unleashing all 600hp, frying the 295/50's! Lotsa fun...
 
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