Jump to content
SAU Community

Recommended Posts

So i have rescently purchased a r33 gts-t s2 1996, it ran fine for a few days until now when i took it for a drive and drives okay, but when i put my foot down and accelerate and hit boost it just gets rough, the whole car shakes, my foot on the acceleration shakes, it feels like the power just dies out.. im no big mechanic guru so i cant really get my head around this, any help will be appreciated! cheers

Link to comment
https://www.sau.com.au/forums/topic/416147-not-hitting-boost-like-it-should-be/
Share on other sites

  • Replies 48
  • Created
  • Last Reply

Top Posters In This Topic

You would be well advised to provide more details. Such as rpm where the bad things start, max revs you can get, max boost it sees, any noises, whether the shaking feels like something mechanical is out of balance or it is a power on-off-on-off-on-off type thing. etc.

First check afm. Take air filter out clean it with some throttle body cleaner and clean the afm the same way. Do this before you do anything else because its the most common issue and easiest fix.

how would spraying the air filter with throttle body cleaner be a good thing? wouldnt you just replace it if standard and if a pod use some compressed air to blow in reverse direction?

I think mental shorthand became the typed word. Expand his instruction to something like "remove the air filter and spray the AFM with throttlebody cleaner".

Of course, that's not smart anyway. As many AFMs have been damaged that way as have been fixed. I would use CO contract cleaner spray rather than carby cleaner.....and be very careful about how I sprayed it.

Sorry should have elaborated. Take off you air filter. If it is disposable get a new one. If it is reusable tap it gently to remove the debris. Then use a soft brush or air compressor to remove the rest of the impurities. Then once you inspect it and are happy with the result remove the soot type impurities with throttle body cleaner or contact cleaner. For the afm, remove it and brush over the mesh with a very soft brush making sure you are holding it so the debris fall away from the centre element. Once satisfied with the result of both sides get some contact cleaner and spray from a distance onto the element to clean it. You can use throttle body cleaner as I have never had an issue. Up to you. If you have contact cleaner also apply to the afm plug. Hope this helps

okay right, first off i should say the bad things started happening around 3000rpm to 4000rpm and beyond that i did not continue accelerating since things got messy, i have a dodgy boost gauge that came with the car and seems to function but id rather not go with it for a correct pressure reading. when i bought the car i did see that the podfilter bracket that holds it, is broken and now its just dangling on the shell, and also the AFM bracket is snapped, so there is not a full seal from filter to AFM to piping, could this be the problem? if so, new pod filter and AFM?

, and also the AFM bracket is snapped, so there is not a full seal from filter to AFM to piping, could this be the problem? if so, new pod filter and AFM?

You mean the outer shell of the AFM is broken? Or the intake pipe is otherwise compromised? This is a serious problem but it might not be THE problem.

How much boost?

What is the ECU ?

Check for any air leaks especially between:

1 - AFM and turbo

2 - Turbo and throttle body (BOV connection, intercooler pipe connections, etc).

I took some photos so i can explain it better:

http://i1272.photobucket.com/albums/y396/Adrian701/IMG_0134_zps7bb973ee.jpg

In this one i found the circled hose being off, and im uncertain what the black box it came from is..

http://i1272.photobucket.com/albums/y396/Adrian701/IMG_0137_zpsea39cd84.jpg

Where im pointing on this, there is a mixture of water and something else overflowing just to the rim of that larger hose, but the hose loops around to that pulley from the left of my hand (water pump?)

http://i1272.photobucket.com/albums/y396/Adrian701/IMG_0133_zpsc99e6ba4.jpg

And in this one, you can see the AFM bracket mount is snapped (previous owner tried to super glue it -.-) the right hand side bolt on the pod filter just pulls out so its not vulcanized in the rubber anymore and the left one is not far from it too, and that F*** off bracket is completely been made wrong side it dosent even bolt on, thats no problem since i can make a new one myself

i have also tightened all my head cover bolts, since they all seem to have atleast another turn to them.. the furtherest ones so closest to the windscreen seem like they have been leaking over the time very slowly

the ECU is stock im pretty certain, and uncertain of the boost :/ i ran my fingers across all the piping and i cant see or feel for any damage/leaks

thanks for all the help again!

I took some photos so i can explain it better:

http://i1272.photobu...zps7bb973ee.jpg

In this one i found the circled hose being off, and im uncertain what the black box it came from is..

http://i1272.photobu...zpsea39cd84.jpg

Where im pointing on this, there is a mixture of water and something else overflowing just to the rim of that larger hose, but the hose loops around to that pulley from the left of my hand (water pump?)

http://i1272.photobu...zpsc99e6ba4.jpg

And in this one, you can see the AFM bracket mount is snapped (previous owner tried to super glue it -.-) the right hand side bolt on the pod filter just pulls out so its not vulcanized in the rubber anymore and the left one is not far from it too, and that F*** off bracket is completely been made wrong side it dosent even bolt on, thats no problem since i can make a new one myself

i have also tightened all my head cover bolts, since they all seem to have atleast another turn to them.. the furtherest ones so closest to the windscreen seem like they have been leaking over the time very slowly

the ECU is stock im pretty certain, and uncertain of the boost :/ i ran my fingers across all the piping and i cant see or feel for any damage/leaks

thanks for all the help again!

wonder if im seeing it wrong but does the top of the boost control device have no hoses? or am i looking at somthing else, pretty sure mine has some vacumn hoses connected to that, second picture where the fingers are, under powersterring reserviour

Edited by SliverS2

yeah i was wondering what that was, so its clearly missing the 2 hoses but i couldnt find the where they would plug in, any thoughts? thanks

from memory, you should have one from the compressor cover, on the side, that will plug in the the solnoid and then the actuator one will also plug in , can you locate them?

im afraid not, could this be related to my initial problem, car getting rough when you put your foot down/ loss of power?

ive listened carefully to the idle as well, and its a bit rough too..

previous owner claimed that the coilpacks are new, so that would be safe to rule out?

Edited by AdrianGTT

im afraid not, could this be related to my initial problem, car getting rough when you put your foot down/ loss of power?

ive listened carefully to the idle as well, and its a bit rough too..

previous owner claimed that the coilpacks are new, so that would be safe to rule out?

It sounds to me like its atleast contributing if not the solution, you have a vacumn leak and you have no boost control so its overboosting by sound of it and hitting massive RnR, connect the lines back up properly and see what happens

from my experience with my own coilpacks, they didnt affect idle they made the engine start backfiring a bit violently at about 4000rpm on high boost with around 200kw , check your plugs and hose clamps too

Edited by SliverS2

thats my problem, im not sure what lines go where, maybe a picture of your setup will help? i searched some links on google and i cant find anything similar

mines an external gate setup so probably wouldnt help, just connect the compressor cover one to the bottem and then from the solnoid connect a line to the actuator and see what happens, your bascially just feeding the pressure to the actuator from the compressor outlet so probably work either way, but expose the actuator under the big flat cover so you can see if it is connected to somewhere or not.. could be just clutching at straws here,

hope that helps

someone chime in to correct if im wrong...

Edited by SliverS2

pictures would help a bunch or a link with something since im not big on the technical words, im tempted to just take the car to my local tuner but then again i dont want to do that just to connect some lines for me, thanks again!

ive also found a nipple with a bolt in it under the purple pipe.. dodgy

http://i1272.photobu...zps3fad0b48.jpg

http://i1272.photobu...zpsd73d5f66.jpg - there is this black thing that im holding as well to which i have no idea what it is either.

could you take my photo and draw a few arrows on paint with what hose goes where, or what hoses i need to get? that would be great! cheers again for everything mate

Edited by AdrianGTT

wonder if im seeing it wrong but does the top of the boost control device have no hoses? or am i looking at somthing else, pretty sure mine has some vacumn hoses connected to that, second picture where the fingers are, under powersterring reserviour

You can see in the same picture he has a boost controller.

Manuel one that is black.

So no his boost controller does not need hoses

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



×
×
  • Create New...