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Fuel Cut When Go Up Hill

YangLIU

By YangLIU,
in Four Door Family & Wagoneers

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YangLIU Rising Star

YangLIU

Posted
Posted (edited)

hi all,

i just went to Wollongong from Sydney today. on the highway with up hill,20-25% flatting on acc pedal, car speed around 100km/s - 110km/s, i always get fuel cut when injector load at 25%-30% (4-5psi on boost), when the issue came, injector load down to 0% then back to normal, sometimes injector load will up to 40%-50% then down to 10% then back to normal. (i got this info from greddy informeter touch). engine will not stall, just got one second fuel cut then back to normal and continue speed up.

when i keep rev up with 20%-25% flatting on acc pedal, after the car got fuel cut and restore back, it will happens again after several seconds. i need to release my right foot then depress again to speed up again.

i just did the main maintenance, change all oil/fluids, new plugs, transgo kits, hiflowed turbo (with EBC runs 17psi), turbosmart kompact, kn oil filter, new fuel filter, constant 12v on stock fuel pump (just blew the walbro pump), 4 new tyres (same size) for about 10000kms (actually there is no shudder when driving on flat highway over 100km/s or brake)

there is no problem if the road is flat or 10% flatting on acc pedal (absolutely it is going slow down when on up hill road).

after back home, i scanned with consult3, there is no error code.

i am not quite sure when i have this problem but i just found it today, LOL. (there is no much up hill highway in Sydney...)

may be the problem is stock fuel pump doesn't contact 12v? any ideas? or time to get emanage?

Edited by YangLIU
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https://www.sau.com.au/forums/topic/460888-fuel-cut-when-go-up-hill/
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BoostdR Mentor

BoostdR

Posted
Posted

The additional load from the hill causes higher boost vs tps vs rpm than the ecu will allow(boost cut). Duty cycle decreasing shows the ECU cutting fuel not the fuel pump having and issue.

Do you run a Throttle controller ?

Matt

YangLIU Rising Star

YangLIU

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  • Author
Posted

The additional load from the hill causes higher boost vs tps vs rpm than the ecu will allow(boost cut). Duty cycle decreasing shows the ECU cutting fuel not the fuel pump having and issue.

Do you run a Throttle controller ?

Matt

Yes, I have throttle controller in my car

YangLIU Rising Star

YangLIU

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  • Author
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I do have a throttle controller. Using the throttle controller normal map fixes it half the time. Changing the max AFM output voltage on my EMU fixes it all the time

i am thinking how stock ecu get rid of this with stock turbo

YangLIU Rising Star

YangLIU

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Posted (edited)

Lol, trifecta

besides throttle controller, is there any help if i remove EBC and swap back factory boost solenoid?

you mentioned "Changing the max AFM output voltage on my EMU fixes it all the time"

for my problem, when i got fuel cut, it was under low boost and i assume my stock AFM didn't get 5v voltage at that time. why changing max AFM output voltage could fix this problem?

Edited by YangLIU
scotty nm35 Grand Master

scotty nm35

Posted
Posted

It's not a 5v cut, it depends which cells you are in as to what the AFM cut voltage is.

If you are hitting 21 odd psi occasionally and still have the stock map sensor connected it can boost cut as well.

Just bumping the boost up on the factory map will cause the ecu to protect the engine, sounds like you are trying to destroy it from 3 sides so don't be surprised if you have gone backwards in power. tuning time is well overdue.

YangLIU Rising Star

YangLIU

Posted
  • Author
Posted

It's not a 5v cut, it depends which cells you are in as to what the AFM cut voltage is.

If you are hitting 21 odd psi occasionally and still have the stock map sensor connected it can boost cut as well.

Just bumping the boost up on the factory map will cause the ecu to protect the engine, sounds like you are trying to destroy it from 3 sides so don't be surprised if you have gone backwards in power. tuning time is well overdue.

i have stock map sensor on the car but blocked the vacuum. anyway, will get tune soon.

btw, is it necessary to get emanage ultimate or just need emanage blue? also is there any plug and play loom or just need universal loom?

so many questions. :nyaanyaa:

scotty nm35 Grand Master

scotty nm35

Posted
Posted

The Blue only adds timing and fuel I think, the Ultimate adds and subtracts.

You need to hardwire the universal harness, either into the stock loom or I can supply a patch loom if you really don't want to cut wires. Not cheap, but I could prewire that for you I suspect, and send it out ready to plug in.

YangLIU Rising Star

YangLIU

Posted
  • Author
Posted

The Blue only adds timing and fuel I think, the Ultimate adds and subtracts.

You need to hardwire the universal harness, either into the stock loom or I can supply a patch loom if you really don't want to cut wires. Not cheap, but I could prewire that for you I suspect, and send it out ready to plug in.

PM sent. :rolleyes:

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