high fuel pressure at idle, need input

[grimreaper]

car is in the sig. compression was a perfect 150 across the board with 2 at 155. plugs 3330 (1 step colder) gapped at .28 vac is perfect and boost is rock solid at 14 psi (wastegate) so motor is in good woring order...

afm screw is about half way out,
no vac car on: 47 psi
vac on car on: 39 psi
car of jumped FP-B+: 49psi

im seeing VF's of 3.5 with these fuel pressures. seems like alot of fuel at idle to only be getting 3.5 and not a perfect 2.25 volts. any body comment on this? only thing i can think is that the 61gt flows a bit more even at idle compared to other guys ct's

dont want to set it to much higher here so any body have a clue to why im having to get the prssuer so high at idle to get the vf's in check?


also when i drop it to 35psi vac on (few less) im still at 3.5volts, just a bit leaner in that range and border line 5v as it will fliker backc and forth between them....:1zhelp:


*update* AFM rades 1900-2000 ohms when the casing tempature is roughly 80 degrees or a bit more... seems right in line with what the manual says

Fuel pressure does NOT increase when i pinch the return hose as hard as i can with my fingers either. gauge twitches a tiny bit at first but not even 1 psi raise.

 

[GrimJack]

J tube bypassed or drilled out?

Walbro fuel pump... how is it hooked up? To the stock wiring, or rewired? Has the 12v fuel pump mod been done?

How's the idle - rpm, smooth / rough, anything odd there?

 

[grimreaper]

J tube bypassed or drilled out?

Bypassed

Walbro fuel pump... how is it hooked up? To the stock wiring, or rewired? Has the 12v fuel pump mod been done?

no 12v mod, stock wiring hooked to wires on the pump cage in tank. HP version as well


How's the idle - rpm, smooth / rough, anything odd there?

smoother since adding more fuel. i could hear a slight miss when it was set at lower fuel pressure.

Also o2 is new with less than a few thousand miles on it. and no codes if it matters.

 

[BillyM]

...mis-calibrated gauge?

Longer opening-time on the 550's than stock?

AFM signal (hz) is lower than it would like.

--billyM

 

[grimreaper]

dont know how to check the injectors other then pulling them and getting them cleaned and flow tested.

ill check the afm hz by the manual, but im not getting any stalling issues, or codes that i thought would signify an afm electronic issue.


and on the gauge, its vented when i read it so it "should" be accurate, it desnt fluctuate though, or anything that would make me second guess it, ill pick up and external one from the parts store and double it check it after work.

anything else?


UPDATES in post #1

 

[grimreaper]

found my error, good to know the air temp sensor works properly

now for the afm, i think she's measured her last bit of air. need to double check the wiring from ecu to connector to make sure no wires are broken.

E1-VC: 156,000 ohms
E1-KS: open circuit

should there be some resistance between E1-KS if its off the car?

 

[BillyM]

...another simple thing that could cause lean running at idle is a vacuum leak.

Have you pressure tested the whole intake?

(I often overlook that, since I'm map-based... Vacuum leaks? Psh, I can run my car straight-throttlebody.)

--BillyM

 

[grimreaper]

never got to that point, was actually on my way to home depot when the car decided it didnt want to run any more

after checking the harness and connectors ( all good from ecu to afm connector) and the bit of info i added above about the open circuit on the KS pin, afm is shot, wont start at ALL with it plugged in but runs great in limp mode with it un plugged