Leaning out after 10psi ??? any thoughts?

Ok so i have these fuel mods:

Walbro fuel pump (capable of 500hp+)
Turbosmart Fuel pressure regulator - FPR-1200
660cc RC injectors

Powered by a Apexi Power FC ECU.

We cant get it past 10psi before it starts to lean out. Had a chat with some guys on another post and found that the Stock map sensor only reads 9.25psi could this be the cause? Maybe upgrade to an aftermarket inline fuel filter? Couple have said Electrical wiring to the fuel pump might need to be upgraded to a larger amp wire?

Just to avoid confusion the car is running fine at 10psi atm. We have set it at this with a healthy tune until i can sort out this issue. All of my fuel mods/upgrades are brand new and have recently been added to the car without issues.

Can anyone shed some light on my darkness to help me figure this out?

Im going to be upgrading the wiring to the fuel pump this week or weekend coming to eliminate that possibility.

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Originally Posted by FastFwd

We cant get it past 10psi before it starts to lean out. Had a chat with some guys on another post and found that the Stock map sensor only reads 9.25psi could this be the cause? Maybe upgrade to an aftermarket inline fuel filter? Couple have said Electrical wiring to the fuel pump might need to be upgraded to a larger amp wire?

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The stock MAP on 92+ readp 10.65psi, under 92 reads 9.25psi. the fuel pump wiring should be fine. Never hear of people upgrading the fuel pump wiring. As i suggested in another thread, buy a 2.5bar MAP sensor, not much at all, see if that fixes the problem & go from there. Hope this helps you on your mission....

Do you actually know the problem is fuel pressure? Have you got a fuel pressure gauge?

from a purely theoretical viewpoint, lol, i very much doubt u have any issues with your pump, regulator or injectors

i doubt changing the wiring to the fuel pump will change anything at all

like DLO01 said, if you are still convinced that it could be a problem with fuel pressure, check definetley

i think its an ecu/tuning issue more than anything....but you have power fc, so maybe tuning problem..

if u get a new MAP sensor make sure its good quality, lol........i have nfi what the limit for a stock MAP sensor is

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Originally Posted by DLO01

Do you actually know the problem is fuel pressure? Have you got a fuel pressure gauge?

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I dont think its a problem with fuel pressure. Yeh i got a gauge.

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Originally Posted by krogoth

from a purely theoretical viewpoint, lol, i very much doubt u have any issues with your pump, regulator or injectors

i doubt changing the wiring to the fuel pump will change anything at all

like DLO01 said, if you are still convinced that it could be a problem with fuel pressure, check definetley

i think its an ecu/tuning issue more than anything....but you have power fc, so maybe tuning problem..

if u get a new MAP sensor make sure its good quality, lol........i have nfi what the limit for a stock MAP sensor is

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Well its cant be the tune, i actually had my tuner having issues with pushing it over 11 psi. We were there trying things to get it working for over 2 hours. Fuel pump and pressure seams fine but it just seams the injectors arnt pushing what they should.

very interestinggggggggggggggggggggggg

11psi is good enough man, wats that like 200kw, lol

already in wheel spinning gear 4 territory, haha

they brand new injectors, so they shouldnt be playing up?

thats interesting man, but wiring on the pump wont make a difference ;) have you changed the fuel filter? silly but hey it could happen!

i would be thinking to change the MAP sensor first caz i would be guessing that would be the main problem.

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Originally Posted by FastFwd

Well its cant be the tune, i actually had my tuner having issues with pushing it over 11 psi. We were there trying things to get it working for over 2 hours. Fuel pump and pressure seams fine but it just seams the injectors arnt pushing what they should.

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Sounds like you are reaching the max the map sensor is able to read.

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Originally Posted by krogoth

very interestinggggggggggggggggggggggg

11psi is good enough man, wats that like 200kw, lol

already in wheel spinning gear 4 territory, haha

they brand new injectors, so they shouldnt be playing up?

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Yer tru but i want to have the ability to run 20-24psi etc for drags and just run like 10psi on street.

Nah brand new injectors soo there fine.

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Originally Posted by lookingforboost

thats interesting man, but wiring on the pump wont make a difference ;) have you changed the fuel filter? silly but hey it could happen!

i would be thinking to change the MAP sensor first caz i would be guessing that would be the main problem.

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Nah i havent, thinking of changing to a nice inline fuel filter.

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Originally Posted by aaronng

Sounds like you are reaching the max the map sensor is able to read.

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get a new one ftw

Do EEt and tell us how u go