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Gtr R34 Bouncing Losing Traction On Boost

v-specjay

By v-specjay,
in Engines & Forced Induction

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v-specjay Apprentice

v-specjay

Posted
Posted (edited)

hey guys just purchased a 99 gtr vspec and am having an issue when i come onto boost starts at about 4.5k rpm and gets worse as u accelerate. it feels like im losing traction and the cars rear will kick out to the right. i plan to taqke it to the shop to get it looked at but was just wondering if anyone had an idea of what it might be. It may be something as silly as a boost leak or something, ive come from an sti and ive had boost leaks before doesnt feel anything like that tho car shakes and feels like its jerking back and forth throughout the rev range. car is completely stock no mods other than pirelli p zeros all round no engine work done. if i let the boost build up slowly it wont freak out and cause the problem only when i hit full boost it will start ripping up the tyres and sliding out. ive checked for boost leaks spraying on ic pipes etc but no luck so far locating the issue could this me a afm issue or something to do with the air/fuel raitos? the restrictor pill was removed by owner in japan and is running 1bar.

sorry if this was a silly question or has been answered elsewhere, i just cant put my finger on it!

(not trying to troll )

Edited by v-specjay
GTSBoy Grand Master

GTSBoy

Posted
Posted

Have you considered that you are now driving a RWD biased AWD car and it could actually be losing traction at the rear simply because it is losing traction?

There may or may not be an alignment problem or worn bushes or subframe mounts etc etc that might be causing it. It doesn't HAVE to be coming from the engine end of the car!

GTRPSI Mentor

GTRPSI

Posted
Posted

If its standard as you claim it shouldn't be doing that.

But if its modded.....fully sik. :)

On a serious note, my GTRs rear use to come out under power, she would crab walk, ended up being the subframe bushes were leaking and i put some alloy C rings in place to stop it, she went straight after that.

v-specjay Apprentice

v-specjay

Posted
  • Author
Posted

Itsat standard vspec height its sitting on original suspension also yes it still has original coil packs. I will have to look into the subframe bushes hopefully something turns up..n yes gts boy i understand that its not a full time awd but this is not just simply breaking traction due to power from the rears its more like when i come on boost imagine like fuel surge bunny hops and makes the car break traction and jerks the car forward and backward similar to what youd feel when you have a large boost leak..soo frustrating!

XKLABA Grand Master

XKLABA

Posted
Posted

It could be the ATTESA system that also activates the rear A-LSD on a R34 V-SPEC needs bleeding

Either way it sounds like the car has some issues, best off getting it to someone that knows these cars so they can give it the once over

  • Like 1
djvoodoo Experienced

djvoodoo

Posted
Posted (edited)

If boost (positive pressure) Is only coming in at 4.5K rpm on standard turbos you have issues... Are you sure this is the case as per your post???

**edit** i think i misread due to punctuation... You are on boost, then at 4.5K rpm you have traction issues

?

Edited by djvoodoo
  • Like 1
sneakey pete Grand Master

sneakey pete

Posted
Posted

It could be the ATTESA system that also activates the rear A-LSD on a R34 V-SPEC needs bleeding

Either way it sounds like the car has some issues, best off getting it to someone that knows these cars so they can give it the once over

Oh i forgot about the fun bundle that the A-LSD is.

GTSBoy Grand Master

GTSBoy

Posted
Posted

Itsat standard vspec height its sitting on original suspension also yes it still has original coil packs. I will have to look into the subframe bushes hopefully something turns up..n yes gts boy i understand that its not a full time awd but this is not just simply breaking traction due to power from the rears its more like when i come on boost imagine like fuel surge bunny hops and makes the car break traction and jerks the car forward and backward similar to what youd feel when you have a large boost leak..soo frustrating!

Ever experienced axle tramp?

  • Like 1
v-specjay Apprentice

v-specjay

Posted
  • Author
Posted

Yep the tyres are all the same size, i think it sounds like axle tramp, never experienced it before but sounds on par with whats going on with mine. Thanks guys and

  • XKLABA i will have to check out the attesa see if it needs bleeding. Could be a combo of all of these things just helps to narrow it down a little.

Cheers for the info guys ill report back after a once over from my mechanic if anyone is curious as to what the problem was.

XKLABA Grand Master

XKLABA

Posted
Posted

If a stock R34 GTR is breaking traction it has a 4WD problem of some sort, or very very shit tyres, if it has a 4WD problem and is a V-Spec it will most likely have an A-LSD problem to

A small air pocket won't kick a code but will slow down the operation speed of the diff and 4WD

v-specjay Apprentice

v-specjay

Posted
  • Author
Posted

Lol. How can it break traction and jerk back and forth.

Axle tramp is like a hopping sensation in the back.

Sti and gtr are WORLDS apart in how they drive

yep im not exactly sure mate feels like a little of both at the same time im assuming it has something to do with the attesa ill take it to croydon see what they make of it

v-specjay Apprentice

v-specjay

Posted
  • Author
Posted (edited)

If a stock R34 GTR is breaking traction it has a 4WD problem of some sort, or very very shit tyres, if it has a 4WD problem and is a V-Spec it will most likely have an A-LSD problem to

A small air pocket won't kick a code but will slow down the operation speed of the diff and 4WD

ye exactly it feels like the torque is being split up unevenly or delayed, i have a feeling your on the money.

Edited by v-specjay

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