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33 Rb25det Boost Problem

r33 dylan

By r33 dylan,
in Engines & Forced Induction

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r33 dylan Apprentice

r33 dylan

Posted
Posted

Hi guys, been searching everywhere for an answer but cant seem to find a pinpoint one so im hoping you guys can help.

Basically when i hit about 4.5-5 revs the car just seems to die in the ass and not want to go anywhere at flat foot but if i creepy up the revs at 1/2 throttle and then 3/4 throttle then flat foot it at higher revs it goes like a rocket but after giving it that little boot full the turbo seems to completely stop working and wont even spool up or flutter for ages unless it sits for awhile or car is turned off.

Now when im flat foot it just feels like its choking and struggles to move through the 4+ revs or even the lower revs when trying to accelerate a little quicker then normal.

also when putting the boost up to say 10-11 psi the turbo always spools but its like the ecu doesnt know what or how to handle this bit of extra boost and just wont go anywhere aswell.

hopefully i have described this decently enough to have you gurus tell me how to fix this issue, as it seems to be a trick to try and put into words how to describe whats happening lol.

specs- rb25det neo, all stock setup except for coilpacks which are probably less than a year old (splitfires), changed plugs less than 2 weeks ago.

car has only recently in the last couple weeks started having this issue and before that it was a fun and reliable car to thrash around.

cheers

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https://www.sau.com.au/forums/topic/459280-33-rb25det-boost-problem/
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Gcjosh Community Regular

Gcjosh

Posted
Posted

Search nazis should be shot, a bit like small dick punctuation nazis...

anyway back on subject, you changed plugs now have issues? Is that the only thing you've done? What's your air filter like? Fuel filter?

Air/fuel/spark [emoji6] check those first

scotty nm35 Grand Master

scotty nm35

Posted
Posted

Either put everything back to stock, or tune the car.

You can't just go bumping the boost up without tuning, it will run like balls and perhaps throw a turbine wheel. It will run even worse if you have a highflow turbo you don't know about.

r33 dylan Apprentice

r33 dylan

Posted
  • Author
Posted

Everything is back to stock, was just driving home from the gym and it seems once the turbo spools up to a certain point and I off the accelerator it just stops working.

Plugs were gapped correctly and I'm under the impression I'll need to go for a tune, was just seeing if anyone has any ideas. I'm very new to the forced induction life, lesrn from

Your mistakes I guess.

Cheers guys :)

Dose Pipe Sutututu Grand Master

Dose Pipe Sutututu

Posted
Posted

Turn you boost down, colder weather means denser air. More "air" read by the AFM means a higher TP Load, and because it's a stock ECU and tune you're hitting cells where timing is absolutely retarded as fk.

Boost doesn't equal TP Load, you might be able to run 10/11 psi in summer or so but when it's cold you'll hit those cells running the same boost.

I suggest you turn down the boost.

r33 dylan Apprentice

r33 dylan

Posted
  • Author
Posted

Turn you boost down, colder weather means denser air. More "air" read by the AFM means a higher TP Load, and because it's a stock ECU and tune you're hitting cells where timing is absolutely retarded as fk.

Boost doesn't equal TP Load, you might be able to run 10/11 psi in summer or so but when it's cold you'll hit those cells running the same boost.

I suggest you turn down the boost.

Have turned boost back to normal but is still having issues
r33 dylan Apprentice

r33 dylan

Posted
  • Author
Posted

Sounds like your AFM has dry joint inside it then. Cut it open and solder the pins first, there is a how to on here somewhere.

A new Z32 AFM and a tune would likely fix it too.

Thanks dude, I had a feeling it might be the afm so I'll go sort out a z32. I appreciate the feedback

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