Jump to content
SAU Community

Recommended Posts

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

Link to comment
https://www.sau.com.au/forums/topic/459280-33-rb25det-boost-problem/
Share on other sites

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

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.

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 :)

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.

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

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

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


  • Similar Content

  • Latest Posts

    • Look for broken wire or bad connector at the motor. Might not be it, but is worth starting there, as it is easy.
    • Hi everyone, I’m having an issue with my R32 GT-R. Sometimes, when the car goes over a bump or experiences some vibration, the 4WD warning light comes on the dashboard. When I check the code from the control unit in the trunk, it shows Code 19 – ETS Motor. However, everything seems to be working fine — if I turn off the engine and restart the car, the light goes away and everything functions normally. Has anyone experienced this before? Where should I start troubleshooting this issue? Thanks in advance!
    • I'm back from the dyno - again! I went looking for someone who knew LS's and had a roller dyno, to see how it shaped up compared to everything else and confirm the powerband really is peaking where Mr Mamo says it should. TLDR: The dyno result I got this time definitely had the shape of how it feels on the road and finally 'makes sense'. Also we had a bit more time to play with timing on the dyno, it turns out the common practice in LS is to lower the timing around peak torque and restore it to max after. So given a car was on the dyno and mostly dialled in already, it was time for tweaking. Luis at APS is definitely knowledgable when it came to this and had overlays ready to go and was happy to share. If you map out your cylinder airmass you start seeing graphs that look a LOT like the engine's torque curve. The good thing also is if you map out your timing curve when you're avoiding knock... this curve very much looks like the inverse of the airmass curve. The result? Well it's another 10.7kw/14hp kw from where I drove it in at. Pretty much everywhere, too. As to how much this car actually makes in Hub Dyno numbers, American Dyno numbers, or Mainline dyno numbers, I say I don't know and it's gone up ~25kw since I started tinkering lol. It IS interesting how the shorter ratio gears I have aren't scaled right on this dyno - 6840RPM is 199KMH, not 175KMH. I have also seen other printouts here with cars with less mods at much higher "kmh" for their RPM due Commodores having 3.45's or longer (!) rear diff ratios maxing out 4th gear which is the 1:1 gear on the T56. Does this matter? No, not really. The real answer is go to the strip and see what it traps, but: I guess I should have gone last Sunday...
    • 310mm rotors will be avilable from Australia, Japan, and probably a few other places. Nothing for the front can be put on the back.
    • The filter only filters down to a specific size. Add to that, the filter is AFTER the pump. So it means everything starts breaking your pump even if its being filtered out.
×
×
  • Create New...