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Discussion Starter #1
Its hard to explain the actual sound the engine is making. Its almost as if its coming from the turbo. Anyways, when I downshift into a lower gear when slowing down it makes the sound...almost a clunking sound. It only happens when I'm not giving it gas and I'm riding the gear during deceleration. Its not always, but most of the time.

Anyone know?
 

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i know exactly what sound you're talking about. the noise makes me sad, so i avoid downshifting as much as possible haha. i second you on this being hard to explain, but what i can imagine creates the sound is the transmission gears' stress. not that it can be a bad thing, but it's just something noticable. for example when you accelerate in reverse, you hear the gear noise. same concept. but that's just my "imaginative explanation". hopefully a good fellow knows exactly what causes this and knows if it's a bad sign or not, so i can get a better understanding as well :p
 

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Does the sound still occur when rev-matching beofre clutch engagement?
 

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Discussion Starter #6
it does...its not the engagement of the gear thats the problem its a deceleration noise after I'm in gear. o_O
 

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it does...its not the engagement of the gear thats the problem its a deceleration noise after I'm in gear. o_O
Ahh... ok
I am thinking its the VDC
If you have an STi a combination of VDC and DCCD
Does the vehicle jerk ever so slightly?
 

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maybe a wee little bit...

is this a bad thing?
If this is the case, and I am correct, it is the electronic stability kicking in. Try turning the VDC off (yellow, one quick tap) see what happens.
If it stops or becomes less prominent when you do this, then yes its normal.
 

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If this is the case, and I am correct, it is the electronic stability kicking in. Try turning the VDC off (yellow, one quick tap) see what happens.
If it stops or becomes less prominent when you do this, then yes its normal.
correcto. i just tried it out. no more ugly noise haha. i'm really starting to lean towards always having vdc off unless i'm in a track/circuit sort of situation
 

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If this is the case, and I am correct, it is the electronic stability kicking in. Try turning the VDC off (yellow, one quick tap) see what happens.
If it stops or becomes less prominent when you do this, then yes its normal.
correcto. i just tried it out. no more ugly noise haha. i'm really starting to lean towards always having vdc off unless i'm in a track/circuit sort of situation
Glad you got it taken care of.
Also if this is the case, leave the VDC off always as it actually hinders the real performance of the vehicle.
VDC is traction control that senses vehicle direction and uses brake, throttle and engine management to help maintain stability.
The components of the VDC system are:
all wheel drive using the VTD system.
When the wheels are spinning without traction or the vehicle is not going in the direction it is being steered, the VDC system kicks in.
Direction: uses brakes to slow down wheels to reduce spin and help control vehicle direction.
Skidding: yaw and steering wheel sensors use brakes to slow down spinning wheels and re-direct power to the wheel(s) with the best traction to re-gain control.
Engine power use engine output to slow spinning by reducing spark to cylinders to cut back power and help re-gain control.
 

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Imagine what all that tries to do when you are already diving into a corner, trying to weight shift, trailbraking, using zero-counter, or all the craziness you actually want to to on the track or auto X to get a good time. I would rather be in control of all aspects of the vehicle wouldn't you? :)
 

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Glad you got it taken care of.
Also if this is the case, leave the VDC off always as it actually hinders the real performance of the vehicle.
VDC is traction control that senses vehicle direction and uses brake, throttle and engine management to help maintain stability.
The components of the VDC system are:
all wheel drive using the VTD system.
When the wheels are spinning without traction or the vehicle is not going in the direction it is being steered, the VDC system kicks in.
Direction: uses brakes to slow down wheels to reduce spin and help control vehicle direction.
Skidding: yaw and steering wheel sensors use brakes to slow down spinning wheels and re-direct power to the wheel(s) with the best traction to re-gain control.
Engine power use engine output to slow spinning by reducing spark to cylinders to cut back power and help re-gain control.
Imagine what all that tries to do when you are already diving into a corner, trying to weight shift, trailbraking, using zero-counter, or all the craziness you actually want to to on the track or auto X to get a good time. I would rather be in control of all aspects of the vehicle wouldn't you? Smiley
100% agreed. no other way to put it. i also believe that it's second nature to counter steer or react certain ways if loss of control of the car. but when the car starts to take care of it, it feels awkward you know, you correcting the position of the car while the car is correcting it, it's almost like contradicting each other haha. also, TougeMonster, any chance you would know if turning the VDC off will turn off VTD or anything else? thanks for great input :D +1 karma
 

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100% agreed. no other way to put it. i also believe that it's second nature to counter steer or react certain ways if loss of control of the car. but when the car starts to take care of it, it feels awkward you know, you correcting the position of the car while the car is correcting it, it's almost like contradicting each other haha. also, TougeMonster, any chance you would know if turning the VDC off will turn off VTD or anything else? thanks for great input :D +1 karma
With the VDC off, the VTD remains stable at 45/55 power distribution even under wheel slip situations.
 

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Discussion Starter #15
100% agreed. no other way to put it. i also believe that it's second nature to counter steer or react certain ways if loss of control of the car. but when the car starts to take care of it, it feels awkward you know, you correcting the position of the car while the car is correcting it, it's almost like contradicting each other haha. also, TougeMonster, any chance you would know if turning the VDC off will turn off VTD or anything else? thanks for great input :D +1 karma
With the VDC off, the VTD remains stable at 45/55 power distribution even under wheel slip situations.
yep. i can hear it slightly. but you were on the money about the sound i was hearing! thanks bro!
 

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100% agreed. no other way to put it. i also believe that it's second nature to counter steer or react certain ways if loss of control of the car. but when the car starts to take care of it, it feels awkward you know, you correcting the position of the car while the car is correcting it, it's almost like contradicting each other haha. also, TougeMonster, any chance you would know if turning the VDC off will turn off VTD or anything else? thanks for great input :D +1 karma
With the VDC off, the VTD remains stable at 45/55 power distribution even under wheel slip situations.
yep. i can hear it slightly. but you were on the money about the sound i was hearing! thanks bro!
You are most welcome. Anytime :)
 

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I also have that same problem but it sounds more like a load on the gears. Most noticable in second only on decel. Tried turning of stab control and same thing?
 

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I also have that same problem but it sounds more like a load on the gears. Most noticable in second only on decel. Tried turning of stab control and same thing?
yeah i still notice it too but just ever so slightly. but i can definitely tell that there's no more jerking, the jerking you can hear AND feel as you're decelerating with VDC left on. i can especially hear and feel the jerking in situations like when coming i'm to a stop from 3rd gear, then downshifting to 2nd. but, with VDC off, i notice very minimal jerking at all and it feels and sounds much smoother. try to experiment with it and get the desired feel you're looking for. hope this helps :)
 

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I also have that same problem but it sounds more like a load on the gears. Most noticable in second only on decel. Tried turning of stab control and same thing?
If it sounds like engine load, then it might be something else altogether. Are you getting the jerking when you down shift and engage?
Ot is it what the OP is stating that the shift has been completeed, and then deceleration?

Might help us a bit more to diagnose. :)
 
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