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I'm Getting Bad Boost Cuts/boost Leak

Richy

By Richy,
in Engines & Forced Induction

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Richy Rookie

Richy

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my r33 gtst is boost cutting or leaking, i'm not quite sure which one it could be but basically whenever i boost more than 5 psi, boost just wont hold, it either spikes at high rpm's or i don't feel the boost at all. For example the other day i set the boost to about 9 psi and at full throttle it spikes a little (not much) to 4/5k rpm and past that it will just start cutting like it doesn't wanna go any further. So now it's set back to 5 psi but i need to get rid of this problem. I've been told so many different things like Coilpacks need to be changed, intercooler could be leaking cos a friend installed it not a mechanic, BOV could be leaking etc.

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daxter Enthusiast

daxter

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Sounds like your fuel cut may be coming on.

Don't use a bleed valve there prone to spiking. And don't let your friends touch your car, get qualified mechanics to do all work.

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mad082 Grand Master

mad082

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do you have a front mount? if you do where do you have the controller taking its reading from? if it is from the bov hose then relocate it. have a nipple installed on the hot intercooler pipe.

what does the cutting feel like? is it a hard start/stop? or is it like a spluttering? if it is a spluttering then try gapping your plugs down, and taping up your coils.

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bubba Grand Master

bubba

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I had the similar symptoms the other day on my 32.. a hose clamp had popped off but the pipe was still in the hose (i.e. it hadn't popped all the way off). Was driving back from the shops and it would start to spool then at 4k it would kind of cut out.. I've had a hose pop right off on the highway once before and could barely keep the thing idling and driving it to the nearest exit was a complete bastard.

This time I could still drive if didn't go over 4k.. got home, popped the bonnet and found a hose clamp where the cooler piping joins the crossover pipe had let go :)

BUT could be the stock ECU's fuel cut happening on your 33 :)

Edited by bubba
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mad082 Grand Master

mad082

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bubba you could be onto something there. if you had a hose that wasn't sitting on right, and once it had a fair bit of force on it it was opening a gap up it would cause a loss of boost pressure and the car to run overly rich, which could be the cause of this issue. it would be worth checking the cooler piping.

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bubba Grand Master

bubba

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Yeah had me scratching my head for a bit, then the clamp just didn't want to stay on the silicon anymore :) luckily I had a spare 100mm of truck cooler hose (shiz cost me $50 for 200mm!)

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Richy Rookie

Richy

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i'm gonna try taking off the intercooler and connecting it straight to the turbo, the cut feels like the airs just spluttering everywhere its spooling but just feels like its going nowhere. i got a stock ecu. I'll post results of the intercooler removal tommorow. thanx

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