Gtr Boosting Problem

[ali-turko]

hey guys

iv got another problem with my gtr and it pissing me off!

ok iv searched and can find what im looking for, except the s13 below my tread has the same problem,

my car is running 15psi with the restictor out, and only has exhaust and 2 airpods.

the car runs fine for bout 20 mins and wont boost past 10psi, and also the bovs are going nuts sounds like there surginging un till i het 3000rpm, i no my afms are fine, tested them and have pretty similar volts.

can some please help me?? i would really aprectate it..

OK IF ANYONE CAN SOLVE THIS PROBLEM I WILL SHOUT A SLAB OF WHAT EVER U WANT.

C'MON GUYS SOMEONES GOTA NO

thx in advance

Edited September 18, 2006 by ali-turko

[95SKY]

hey guys

iv got another problem with my gtr and it pissing me off!

ok iv searched and can find what im looking for, except the s13 below my tread has the same problem,

my car is running 15psi with the restictor out, and only has exhaust and 2 airpods.

the car runs fine for bout 20 mins and wont boost past 10psi, and also the bovs are going nuts sounds like there surginging un till i het 3000rpm, i no my afms are fine, tested them and have pretty similar volts.

can some please help me?? i would really aprectate it..

thx in advance

^ Ive got the same problem same mods aswell. Im keen to find out to.

[ali-turko]

anyone?

[GTRgeoff]

I'll take a look when we do the swap.

[ali-turko]

cool thx buddy

[ali-turko]

c'mon some one would have experienced this problem b4...

[paulr33]

what air intake?

---> stock box and filter? stock snorke? twin pods?

tried ecu reset?

tried running normal levels of boost instead of 1bar?

[SXR]

15psi boost a bit high for a stocky.

Check all your intercooler joiners?

[LOOF]

What mods have you got mate?

[fr0st]

Are you AFM's maxing out? Could be boost cut at 15psi

The fact that it happens after 20 minutes suggests that its probably a vibration or heat issue rather than something like a broken hose or connector.

Are you running pods? are they supported by a bracket?

It could be the connector on the AFM's, the solder inside the afm is known to crack with vibration but seem fine at idle.

Just testing the voltage at idle isn't really a measure of how well your AFM's are working.

[ali-turko]

blitz airpods, exhaust system all the way through with no cat, and running 1 bar on the standard solinoid

[paulr33]

does it compressor chuff when coming on boost?

like think of the vl turbo flutter noise on gearchange or throttle close

is it like that, when coming on boost

[ali-turko]

yer sort of, its like when starts hiting boost (its like chu chu chu chu ect...) untill im over 3000rmp but only the that stupid sound stops and still it dosnt go ova 10psi untill i restart the car

[paulr33]

no sorry ive explained it wrong

compressor surging known and heard as "fluttler" when coming on boost is a result of the pressure in the manifold going past the compressors effiency, ie the compress map says in the best scenario it can flowing at best 16psi of compression, but for some reason the manifold pressure is say 18psi so the compressors surge resulting in vl turbo style flutter on boost, ie: the compressors are out of effeiency and surging / erractic operation / wobble

comrpessor chuffing is usually caused by aftermarket pods and piping kits to the stock turbo's. basically the air reverbates and chops past the airflow meter, so it runs like a bitch. this is common with say 2530s and custom piping and pods. not very common on stockers i dont think, but certainly possible

[ali-turko]

and also it mat not do it for couple of days and then suddenly it will come back, iv also re-solder the afms, and plug one of those ecu data things in and the afms seemed to be fine, but i no my rear 02 sensor is stuffed and will b replacng asap!

[paulr33]

my advice would be to drop the restictor or whatever you have done and go back to direct actuator mode, that is stock boost. that way it should be a clean slate. then if you can replicate the problem then something is wrong with turbo setup or intake.

if #1

compress surging, try lowering the boost, see if that helps

the compressors shouldnt surge under normal conditions

could indicate compressor failure, out of balanace or chopped wheels

again assuming the same problem occurs on say stock boost

if #2

try seperating the pods or putting a shitload of pipework between one of them or both them, try like some good sized pool shop vacuum hose for one of both of the pods, try bending the pods intake pipes. anything to alter the intake path of air to the compressor inlet snout

again this is only what i think, it doesnt mean im write or correct at all

[ali-turko]

so u got any suggestion on how to fix it, theres a slab in it for u if u no how to

[ali-turko]

umm i use to have the hks pod filters with different adaptters and still had the same problem, i dont have the resrictor coz as the car came with out one,

but what i understand is y dose go away after i restart the car for a few seconds?

[paulr33]

as a brutal hack / test try undo'ing the pods and just leave the turbo's open mounted (jap style) does that change anything?

id almost %100 say its the pods / pipework somehow

[paulr33]

and revert it back to stock boost

stop messing around with 1 bar boost

its likely to go bang when you are testing various things