What rpm does it happen at?? Sounds like the gr stumble
Most likely culprit? Rolling off throttle produces a pronounced burst of power.
Car experiences a quick burst of forward power when you smoothly, but quickly roll off the throttle, mainly after accelerating in 3-6th at 3/4 to full throttle.
It's as jolty as if you double tapped(floored) the throttle in 2nd gear at 4k rpm, but this should not happen when you are smoothly rolling off throttle.
Is this potentially a BPV issue? I have searched forums, and there are many possible explanations, but to me it seems more like the throttle position sensor "thinks" I have pressed the pedal at some point while releasing it. That's kind of what it feels like.
How do I have to describe this to a stealership to get the correct areas looked at?
So many annoyances with this car I never had in my 05.
It's as jolty as if you double tapped(floored) the throttle in 2nd gear at 4k rpm, but this should not happen when you are smoothly rolling off throttle.
Is this potentially a BPV issue? I have searched forums, and there are many possible explanations, but to me it seems more like the throttle position sensor "thinks" I have pressed the pedal at some point while releasing it. That's kind of what it feels like.
How do I have to describe this to a stealership to get the correct areas looked at?
So many annoyances with this car I never had in my 05.
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subscribed. I actually felt that on some of my previous cars... but it shows more on the sti.
Really curious to know what's the reason....
Really curious to know what's the reason....
I thought it was largely due to the hardcore transmission
I was trying to figure out the RPM range recently, seems most often in 3rd between 3500-and before hitting 5k. I am going to try to catch it on video then figure it from there, but it's raining today so I may wait a day.
It's really annoying, and I was looking for a few parts I could try that may be to blame. Seems like a sticky or overly stiff BPV spring could be to blame.
It's really annoying, and I was looking for a few parts I could try that may be to blame. Seems like a sticky or overly stiff BPV spring could be to blame.
dealership trip would be my suggestion. have you checked to make sure nothing is getting jammed around the gas pedal? floormat, etc.
I have experienced something similar a couple times. I remember because of how odd it felt. I believe I was on an off ramp going from like 70 mph down to 40 mph or so. It definitely felt like my car was accelerating while I was rolling off the throttle for a second or two.
Purely conjecture here, maybe the Air/Fuel mixture could become better while slowly letting off the throttle under high boost leading to more power??? My STi's stock dyno has A/F all over the dang place.
Purely conjecture here, maybe the Air/Fuel mixture could become better while slowly letting off the throttle under high boost leading to more power??? My STi's stock dyno has A/F all over the dang place.
It does feel like it's burning what is left from what I ordered from the gas pedal... As if too much fuel was sent to the engine, so it has some left when slowly/lightly letting off the throttlePurely conjecture here, maybe the Air/Fuel mixture could become better while slowly letting off the throttle under high boost leading to more power??? My STi's stock dyno has A/F all over the dang place.
... sounds strange but i'm just trying to describe it...
My guess is AFRs may be off (rich or lean) at high throttle. As you let off the accelerator, AFRs go to the ideal value and make more power.
mm it could be something less complicated like afrs. are you on a stock map? I can almost be certain what youre experiencing is the overly complex way the stock ecu calculate how much torque to request. In your 05 you had a mechanical link from your foot to your TB. so it was less complicated, your car saw more air by more throttle % so more fuel. Now you have your foot connected to essentially a dimmer switch attached to a computer attached to the TB.
Depending on your tune, you could have the same requested torque for 80% throttle to 100% throttle but because you're at a lower % percentage your ecu could be requesting more timing. So to sum it up, I blame dbw. because it really doesnt matter how much you're stepping on the pedal, depending on your settings your car could be requesting full throttle at any % throttle input from your foot. I hope that made sense, just a theory, cause it happened to me when i went from my evo8 to my sti. its almost like a sticky TB if youve ever experienced that
Depending on your tune, you could have the same requested torque for 80% throttle to 100% throttle but because you're at a lower % percentage your ecu could be requesting more timing. So to sum it up, I blame dbw. because it really doesnt matter how much you're stepping on the pedal, depending on your settings your car could be requesting full throttle at any % throttle input from your foot. I hope that made sense, just a theory, cause it happened to me when i went from my evo8 to my sti. its almost like a sticky TB if youve ever experienced that
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