Jump to content
SAU Community

Recommended Posts

Hi buddies,

just changed high flow turbo and spark plugs.

now i found there is random fuel cut problem:

1. when keep around 40% throttle on acceleration and get around 8-10PSI. sometimes i will get fuel cut once suddenly, boost pressure is gone. at this time, if i press acc pedal a bit more deeply, and make more throttle, then the car will keep acceleration and make more boost.

2. when cruise on motoway at 110km/h, just keep around 20-25% throttle on acceleration. it is about 2500-3000rpm and around -5PSI. sometimes i will get fuel cut too, just suddenly feel fuel cut and boost go down to -15PSI. I need to press acc pedal more deeply then the car will accelerate. it makes hard to cruise at 110km/s. i found there is no problem when cruise at 80km/s,90km/s,100km/s.

all fuel cut problem is just a second. all i need to do is press acc pedal more deeply

i keep my eye on boost gauge and AFM voltage, no problem when i got fuel cut.

any idea for this? :woot:

Edited by YangLIU
Link to comment
https://www.sau.com.au/forums/topic/459213-fuel-cut-when-cruise/
Share on other sites

Just because you have it doesnt mean thats why. The P0235 code is unexpected overboost. Clear the code and see if it helps. I had a hdi ebc and didnt constantly have the code.

i heard this from somewhere:

if the car is cold, then stock ECU will not allow high boost.

so if you are running EBC, you will easily get P0235 error.

but actually when i got fuel cut, the boost is less than 12PSI. i think there is no overboost?

how about remove/block stock boost sensor (for stock boost controller, not for the gauge)?

Edited by YangLIU

I have removed the gauge boost sensor. I still have the boost sensor that is near the bov. Have you taken your car to a mechanic or nissan to run a consult on it.

i haven't ran on consult. I just run cell code procedure every time. any difference between consult and cell code procedure?

i think the problem is not related to stock gauge boost sensor.

Edited by YangLIU

Sounds like AFM or boost cut. Both can show up at weird times as the turbo is much larger now, more airflow for the same boost. Definitely get it on a Consult3 and let us know. If there is no real error showing up, it could just need a tune as it's hitting parts of the map it was never supposed to.

Which highflow did you go for? It might be time for an Emanage...

Sounds like AFM or boost cut. Both can show up at weird times as the turbo is much larger now, more airflow for the same boost. Definitely get it on a Consult3 and let us know. If there is no real error showing up, it could just need a tune as it's hitting parts of the map it was never supposed to.

Which highflow did you go for? It might be time for an Emanage...

actually i got this GCG highflowed turbo from a mate, not quite sure how they highflowed it. GCG just told me both intake and exhaust end get highflowed.

i haven't got boost/AFM cut when hit 19-20PSI. my problem always happens when boost at around -5PSI or 8-10PSI.

i cleaned P0235 error code and lower the boost level a bit on EBC.

i saw the stock boost sensor is before throttle and boost sensor (for stock gauge) is at the end of manifold (after throttle). I connected my EBC with boost sensor (for stock gauge) together at the end of manifold. im thinking shall i move stock boost sensor to the end of manifold too with EBC together, because the boost level before throttle is a bit higher than manifold (after throttle)

post-137368-0-21147000-1440556687_thumb.jpg

Edited by YangLIU

Only the MAP sensor on the BOV pipe is causing the code, and it means the sensor is seeing 21psi or more. Looks like your gauge is out by a fair bit.

The cut will be AFM, it isn't just a voltage cut, it cuts at lower voltages depending on the cell it's in on the map at the time.

Only the MAP sensor on the BOV pipe is causing the code, and it means the sensor is seeing 21psi or more. Looks like your gauge is out by a fair bit.

The cut will be AFM, it isn't just a voltage cut, it cuts at lower voltages depending on the cell it's in on the map at the time.

from EBC, i never hit 21psi, so i assume move MAP to manifold could resolve P0235 issue?

for AFM cut, i need to scan with consult3 later

Edited by YangLIU

With a Highflow you should not really be trying for boost over 19psi on the standard injectors and fuel pump. When I had my 30/71r I only ever ran 17PSI.

just saying

sweet!

any idea for the boost/afm cut when cruise on motoway or 8-10psi boost.

Edited by YangLIU

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

    • Join SAU NSW for a flame-grilled feed & flame-spitting cruise! Sunday 17th August 2025 3:30PM Meeting Archies Flame Grille Sylvania Waters 4:45PM Cruise Departure 5:15PM Arrival at Cape Solander Kurnell Meet Location: Archies Flame Grille Final Destination: Cape Solander Kurnell *Disclaimer* There will be a lead and follow car so no one should get lost. If you would like to attend or bring others along please put your name down and a +1 as numbers will be needed prior! This is NOT a race and we will all be adhering to all road rules. If this is what you want please come to one of our many track days. This is an official SAU:NSW event and will be run under a CAMS permit. One of the things that really sets our club apart is our commitment to being true enthusiasts. When on normal roads we strive to maintain good relations with the authorities as well as the public in general. When attending one of Skylines Australia NSW events please try to: • Be aware of surrounding environment and act accordingly. • Drive courteously on the state’s roads as a true enthusiast should. • Understand how important it is to maintain the good name of SAU NSW and thus, treat others accordingly. • Any misbehavior will not be tolerated and you will be asked to leave.
    • Yeah good luck out there! Will be good to see a mighty GTST going harder than the GTRs
    • i will be there 😁
    • Hello!  i just finished manual swaping my r34 skyline with a r33 rb20de box(RB71C)box  When the car is running it squeaks crazy loud and it was smoking from the gearbox area. The gearbox is fine it was tested. The clutch slave cylinder seems like it doesn't fully releases the clutch. I want to ask if this noise is from the throw out bearing or could it be the clutch assembly or disk att.xFliq87Gzw6kImKBVqDebXkj0fBqymk0JaYeP3_3SlM.mp4
    • A few small updates since the previous post and lessons. I decided to do a little interior light upgrade on the 110. I quite like the iilumo items, even if they're a bit of a premium over other brands. You'll also note the Stedi Fogs, that will go into the S15 fog lights as I needed to match the bulbs since I got the new ones earlier. I hope they fit as the body is quite a bit longer than your normal bulb.  Annoyingly, I managed to trip the fuse, which normally wouldn't be an issue until I located the fuse. I can't say I've ever come across this. I had lucked out that someone nearby had a spare, but oddly enough Toyota dealerships seem to keep this in stock. I ordered some to keep in my stash and as luck would have it, someone else nearby tripped the same fuse so I passed on the favour.  I also did a little service on the 110 ahead of some additional work coming up. It's been annoying that Goleby's stopped carrying this particular HKS filter for the 110, so now I need to keep them on order from Japan. I also took the opportunity to install a bash plate and number plate riser. The plate riser is such a cheap but nice fix to help really tidy up the car. I'm tempted to now also replace my headlights, on this car. Both items were from Project Aero.    I also needed to replace the rear tyres on the 110, and after trying to get it aligned learnt that I need to replace some bushes in the front end, so that's next.  Closing out this update with a nicer picture as always! 
×
×
  • Create New...