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R33 Gtst Surging Under Heavy Boost

aphexcloud

By aphexcloud,
in Engines & Forced Induction

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aphexcloud Apprentice

aphexcloud

Posted
Posted

Hi all

new to the forums and owning a skyline(first one)

i had an issue the second day of ownership :angry: was very unhappy jan,

but it turned out to be that the previous owner had decided to use carby fuel hose from the pump to the top of the fuel tank instead of using proper efi hose

and it burst in the tank, had that fixed and now when i am at WOT i feel a bit of surging (the car is manual(converted)) and is running 12-13 psi of boost (bought like this)

std intercooler car came with a exhaust haven't had time to measure or check brand

i am going to try turning down boost before exhaust wheel shits its self but wondering if any one had any other ideas as to what could be causing this

regards

aphex

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Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

describe your surging? I think you're mistaking it with R&R.. the car just hits a brick wall and comes back to life and hits another brick wall...

Too much boost buddy for the stock ECU, it just falls into the wrong cells and bam massive timing pull. I even get that at 0.8bar on cold nights, I just run 0.7bar all day

AngryRB Grand Master

AngryRB

Posted
Posted

Hi all

new to the forums and owning a skyline(first one)

i had an issue the second day of ownership :angry: was very unhappy jan,

but it turned out to be that the previous owner had decided to use carby fuel hose from the pump to the top of the fuel tank instead of using proper efi hose

and it burst in the tank, had that fixed and now when i am at WOT i feel a bit of surging (the car is manual(converted)) and is running 12-13 psi of boost (bought like this)

std intercooler car came with a exhaust haven't had time to measure or check brand

i am going to try turning down boost before exhaust wheel shits its self but wondering if any one had any other ideas as to what could be causing this

regards

aphex

are you sure it is a stock turbo? could it be something else eg a 2876?

AngryRB Grand Master

AngryRB

Posted
Posted

stock turbo would be snapped in half before it could reach its surging limit. might've been afm dirty or miss firing.

The type of surging ive heard is not mistakable, has a distinct sound, take the intake pipe off to see if the compressor wheel has left a grove in the cover, my brothers skyline turned out to have a gt2876, it has a line carve out of the compressor cover.

Maybe inspect the fuel tank for debris and change fuel filter a few times.

aphexcloud Apprentice

aphexcloud

Posted
  • Author
Posted

cheers all for the reply's

i have dialled it back to 10 psi and it has improved but is still there.

When hot the vehicle hesitates/surges i have tried 98 and 100 ron fuel

i thought it might be a battery problem so i replaced to no avail

will pick some contact cleaner for the maf and a fuel filter as well as some sparks tonight

mods: sh*$y drift boost controller, stock BOV, stock intercooler, pod filter

PS: the vehicle smells very rich after snapping the throttle open

regards

aphex

aphexcloud Apprentice

aphexcloud

Posted
  • Author
Posted (edited)

cheers all,

i have cleaned maf sensor with ecc it improved the issue a little but it is still there.

any 1 have any ideas on how to free the stuck rubber hose on the fuel filter (tried bottle nose pliers but don't want to munch the fuel hose) it looks as if it has been on there a while

i also have injector cleaner but dont want to use it till i have a fresh fuel filter in there.

have found the issue is evident in low gears under accel (any) once in 4th-5th at 80km/h-100km/h it will pull fine

ps. what does RnR stand for?

regards

andreas

Edited by aphexcloud
GTSBoy Grand Master

GTSBoy

Posted
Posted (edited)

i wasn't looking for an explanation.

i was wondering what does the Acronym mean... so i could do some research on it

http://lmgtfy.com/?q...esaustralia.com

5th hit, and that's using the less common RnR version rather than R&R.

Edited by GTSBoy
MagicMikeZ32 Veteran

MagicMikeZ32

Posted
Posted

cheers all,

i have cleaned maf sensor with ecc it improved the issue a little but it is still there.

any 1 have any ideas on how to free the stuck rubber hose on the fuel filter (tried bottle nose pliers but don't want to munch the fuel hose) it looks as if it has been on there a while

Cut it off and replace it.

Plattsy Grand Master

Plattsy

Posted
Posted

Yeah, my point was given that you had been told it was R&R, you could have googled it for yourself in less time than it took to ask. I'm just trying to discourage the spoonfeeding mentality on forums.

why isnt that what we are here for? to offer help, support and advice to people that dont know very much.

god knows what you did before google my friend.

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