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Hey Guys,

I've been searching High and Low for the answer to my question..... Why don't I have any boost, even spooling until over 4000rpm or more?

I'm very new to turbo's and i've only had the car for around 2 weeks. One of my mates came for a drive with me (him being in previous skylines before) and said It just didn't have the same kick back as previous ones. Then I picked up my car after getting a front and rear wheel alignment, and the fella asked if I was running the car with minimum boost? or none at all? He said It didn't feel like any of the other ones he has been in!?!? :thumbsup:

The car has a pod filter and after market intercooler installed. Along with yellow jacket coil packs.

My questions are,

Should it have some boost even when cruising? in all gears?

Should the first stage kick in or around 2500rpm in most gears?

Should I just buy a boost tap?

Does anyone have any other ideas on what and where I should start to look? I'll post up a video of my driving it, viewing the stock gauge. Also I'll post up a picture of the vacuum hose setup near the boost solenoid (think thats the name).

Cheers in advance peoples

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P19-11-10_18181.jpg

This is the vacuum hose setup.... that red hose should go to the Intercooler yeh?

http://s49.photobucket.com/albums/f296/ske...-11-10_1810.mp4

Sorry for the shit video guys.

Edited by skeg_man

Trace that vac line back, it should attach to the back of the intake plenum.

From the video you are not getting boost at all.

Does it sound like a diesel when the bonnet is open? Open the bonnet, rev it up and down

you should hear a nice intake and exhaust note. There shouldn't be any roughnes. If there is, maybe

mani gasket or turbo to mani.

Alternatively, take the cat off and see if there are bits of wheel in there. Though, there would normally be a grinding /

strange sound from the turbo if that was the case.

Thanks for the input guys. Im thinking there is a vacuum line prob too. The turbo seems fine. No crunching sounds or grinds. I'll have to unbolt the exhaust and check it out. When I changed over the intake pipe, the turbine in there looked all good. Alright guys, i'll suss it out over the w/e.

The red line leading into the charcoal filter thing.... that should be into the intercooler yeh?

Does you car blow black smoke and stall/run like shit at idle?

Also check your wastegate actuator, it's that rod thing on the side of the turbo's hot side, check the rid hasn't popped off or anything.

Car doesn't blow any smoke at all and idles great. I checked out the actuator and the"rod thing" hasn't come off or anything. The actuator looks a little tired looking tho. I'm gonna get a replacement tomoz I think.

I contacted the guy that I bought the car off and he basically said that it might need a reco. Bit suss if you ask me.

Can someone confirm with me;

1. Boost should be present just driving around normal? 3psi or so? not just at WOT?

2. The red vacuum line I've posted a pic of should be fine there? or should I plumb back into the intercooler?

Cheers

Watching the video, I did not see positive boost once, only atmospheric pressure afew times... If the gauge is true, then what you have right there is a naturally aspirated rb25det, in my opinion the turbo has lost a wheel (I'm not good with R33s, I believe they have a ceramic wheel with a nylon or was it plastic compressor wheel?)

Check ur catalytic converter isnt melted. Then take the line off the wastegate and go for a carefull drive. This should make boost extremely quickly and unlimited boost so only gIve it a really short boost to see if its quicker and there is a fault with ur wastegate vacuum setup.

But

check the cat 1st. Might be melted

its probably just a vac line unplugged or not setup properly

before you go undoing all th exhausts and crap like that check the basic vac lines

find another R33 gtst near you and check how theirs is setup

Well looks like I found the problem maybe..... there must be a leak in the stock gauge line? I just finished installing a DEFI boost gauge and that is reading PSI no worries. The boost seem to be a very smooth incline, not sudden and I think thats what has been throwing me off. The boost +psi reading comes on fast when flooring it. Also much so now after doing the "stock solenoid" DIY.

Can anyone Direct me to the stock gauge vacuum line? I would like to replace it if possible.

I want to say thanks to everyone thats helped me out. Awesome forum to be apart of. :)

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