Leaning out after 10psi ??? any thoughts?

[FastFwd]

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.

[VTECnique]

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?

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....

[DLO01]

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

[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

[FastFwd]

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

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

[FastFwd]

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

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.

[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?

[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.

[aaronng]

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

[FastFwd]

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?

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.

[FastFwd]

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.

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

[krogoth]

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

get a new one ftw

Do EEt and tell us how u go

[krogoth]

http://www.bosch.com.au/content/language1/html/4596.htm
bosch good quality stuff

[DLO01]

Heres a Hondata Map Sensor.
http://hondata.com/4barmap.html

Can also get the Omnipower ones too.
http://www.omnipowerusa.com/product.asp?P_ID=133

[CRXer]

surprised your tuner didnt pick up on that......
guess he aint getting paid to build a working motor

stock map will read to 11psi,u r losing resolution on the sensor & the ecu just dont know what fuel to dish out,get a 3bar MAP now if u want to push out to 20psi

if u r going to 20psi,upgrade the pump wiring,for the cost of 3m of wire & an hour to install it,be better than having your tuner sitting around at $XXX/hr scratching his head again,expensive people to have standing around goin thru your setup tryin to solve little issues.
stock honda wiring was not designed to spin a high pressure pump & keep it at a decent working voltage,the pump will either fail to deliver what u want from it or u will prematurely age the pump by overworking it.

[FastFwd]

wont i only need a 2bar map sensor considering 2bar is 29.4psi (1 bar = 14.7psi x 2 = 29.4psi)

3 or 4 bar is a little excessive. lol 4bar is 58.8psi... i could take my eg to the moon if it could run that amount of boost.

[CRXer]

MAP is manifold "absolute" pressure,meaning read from perfect vaccuum=0psi

atmospheric is already 14.7 psi of your map sensor=1bar

14.7psi boost=atmo + 14.7=2 bar
29.4psi boost=atmo + 29.4=3 bar

u can get a 2.5bar,but thats not leaving u much headroom ontop of 20psi,so id just get the next size,but thats up to u.

[FastFwd]

MAP is manifold "absolute" pressure,meaning read from perfect vaccuum=0psi

atmospheric is already 14.7 psi of your map sensor=1bar

14.7psi boost=atmo + 14.7=2 bar
29.4psi boost=atmo + 29.4=3 bar

u can get a 2.5bar,but thats not leaving u much headroom ontop of 20psi,so id just get the next size,but thats up to u.

Ahhh k,

yep so i will need a 3bar map sensor.

[VTECnique]

MAP is manifold "absolute" pressure,meaning read from perfect vaccuum=0psi

atmospheric is already 14.7 psi of your map sensor=1bar

14.7psi boost=atmo + 14.7=2 bar
29.4psi boost=atmo + 29.4=3 bar

u can get a 2.5bar,but thats not leaving u much headroom ontop of 20psi,so id just get the next size,but thats up to u.

So, if the stock MAP can only read upto 10-11psi, that would make it atmo + 11 = 25.7psi, whats that about 1.5-1.8bar?

[CRXer]

stock MAP is a 0-5Volt sensor,
atmo works out to be about 3V,so u got 2V of boost left on it.

heard figures of 1.8bar & 11psi being tossed about all the time,never tried it myself,so couldnt really confirm any of them.

[Riced_Civic]

so was it the injectors??

if so ive now know of 3 sets of RC injectors fail in a span of 2 weeks including my own

[FastFwd]

so was it the injectors??

if so ive now know of 3 sets of RC injectors fail in a span of 2 weeks including my own

Nah well the injectors seem to be running fine upto 10-11psi but im the stock map sensor fails around that time so im thinking it has to be that.

[Riced_Civic]

ahh kk

[spardikis]

just something ekse for safe keeping i always try n use -
make sure the fpr vac line is independant - ie nothing else is running in line with it
that way at least the fuel pressure vac line shouldnt have any interferance
good luck

[FastFwd]

Ok so a guy on here is selling a 3bar map sensor but its a generic one. Apparently it has the 3 wires which need to be custom wired to the honda wiring but he said it will work fine. Do you guys see any problems with this? has anyone else here got a generic map sensor installed? is it better for me to get one to suit a honda?

[fat_85_civic]

it should be fine, all map sensors are practically the same, they just change their voltage linearly from 0 to 5V.

[Noobs_for_life]

I've got a 3bar sensor if you would like to swap for your stock one, i pulled my turbo off last week and don't need the 3bar anymore, & i'm in Wanneroo :)
Steve

[FastFwd]

Done steve... Lol...Wanneroo also, im in carramar. ill PM ya

[FastFwd]

Guys if i change the map sensor to a 3bar will i need any tune etc to make the car run?

will it be exactly the same but will read upto 3bar?

just wnat to know cos steve is gonna swap me his and i wanna be able to drive my car after i install the 3bar.

[CRXer]

yes,retune in order
it will be reading 0-3bar over a 0-5V range,
instead of 0-1.8bar over a 0-5V range

just take the 3bar with u to the tune & swap it

[FastFwd]

Noobs_for_life (steve) above has one he wants to come around and swap which will leave my civic undriveable.

[CRXer]

what management u running?

has he got a data sheet on the 3bar or know what brand it is?

[FastFwd]

what management u running?

has he got a data sheet on the 3bar or know what brand it is?

Im running Power FC

im not to sure what brand or anything yet. was gonna look into it

[Limbo]

should be able to program the PFC to use the map sensor. It should adjust the fuel maps accordingly, you might just have an issue going up higher.

BTW... i notice my PFC can read boost, it has it in mmhg watever that reading is.

[CRXer]

Im running Power FC

im not to sure what brand or anything yet. was gonna look into it
do u have a hand controller?

def gotta find out the brand or specs,otherwise u'll have to do some bench testing....

[FastFwd]

do u have a hand controller?

def gotta find out the brand or specs,otherwise u'll have to do some bench testing....

Yeh i have a hand controller...

still finding out the specs.

[CRXer]

if u can find the MAP settings menu,u can adjust it yourself,allthough i would verify any changes u make with your tuner before goin testing on full boost.

u will need the scale & offset of the new MAP sensor