Fuel/tuning Issue

[nisskid]

alright, another thread, starting to get old i know. but an issue has appeared.

the issue started a few days ago, but ill start from the very start. the first time i drove the car i noticed that sometimes the fuel pump would get really loud, but be quiet other times, completely random too. the noise doesnt sound like ur normal average healthy fuel pump buzz either.

anyway, last few days ive had big issues with running out of fuel really quickly, even before the fuel light comes on. the first time it ran out i put in like 20 litres and within about 40k's of driving it was empty again. when it runs out it runs out differently to what im used to as well, a consistent miss appears, until eventually breaking down and not starting, or idling rough. same story the 2nd time it ran out, 10 litres in, got me barely more than 10k's before it wouldnt start. i thought this was just a fuel leak, as there is both a burnt and unburnt fuel smell in the air, certainly last night when trying to start it there was a strong wiff of unburnt.

now today i go to put some fuel in it, and the thing is just breaking down under load consistently, even with probably 20ltrs or more in. around 7% inj. duty it starts breaking down. one thing i noticed though, is i think my PowerFC reset overnight, i had a fair few people in the car and something may have happened, not sure. but all my monitor settings were reset etc.

i cant think of anything else worth mentioning, maybe that the knock is still sitting at max of 13ish? also as far as the fuel system goes, apparently it has a adj fuel press regulator, and sard inj (unsure of size). fuel pump is unknown, but im thinking of pulling it out regardless and checking if it's stock, if it is i can pretty much be guaranteed it's the issue, but id still like to get opinions first as it isnt exactly easy to work on my car here.

cheers

[STATUS]

pump is too high or swinging around?

bit hard as im not able to look @ it.

[nisskid]

pulled out the pump today, not sure what it is, has a nissan symbol on it which makes me think its stock (RB20 or RB26), but its been so long since i pulled mine out at home to replace with an 040 i cant remember what im looking at.

numbers and details on the pump are as following:

A42-621 B70

JECS

3217

pics:

[rob82]

Sounds lean - I reckon you've got a fuel leak between the rail and pump to go thru that much fuel!

[nisskid]

if that was the case the car wouldnt the car struggle to start every time it's been sitting because the lines would be dry? it starts fine, it's generally after a bit of a drive it runs out of fuel.

im starting to think it's a separate issue, maybe the powerFC is in a limp mode or something, i dont know, what could cause u to lose ur tune, or for the powerFC to go into a failsafe mode or something?

another suggestion has been made that maybe it's the vacuum lines to the fuel regulator or something? causing issues with picking up the fuel?

not sure, cant go check atm as it's snowing hard here. thats also another point i probably should have mentioned, the car has been driving around in cold weather for the last few weeks, as low as a few degrees below freezing.

[nisskid]

also, if it was running lean, should i notice a raise in knock? there hasnt been a significant rise in knock.

[MBS206]

That pump looks non standard, mayb 044, definitely not an 040.

Looks like an abomination of a mounting setup though... I'd fix that up first...

[nisskid]

been searching the part numbers, and looks like it might be a R32 GTR pump, going to confirm soon, so focus is back on the powerFC for now.

one thing i forgot to mention is before it started to hesitate, since ive had the car its hunted on idle, up and down as soon as the car heated up (and came off cold start), now since this hesitation has started, the car idles perfectly, or at least did for the drive i took it for the other day. this is what makes me think its a tune issue.

[Swiper the Fox]

That pump looks non standard, mayb 044, definitely not an 040.

Looks like an abomination of a mounting setup though... I'd fix that up first...

i lol'd

[Tangles]

you have a fuel leak IMHO

[geraus]

Check your fuel voltages? something got to do with fuel cuz

[nisskid]

you have a fuel leak IMHO

yeh it sounds like that's the case, but would that attribute to the consistent hesitation at the same engine load each time? if im honest it feels electrical, not like fuel starvation. im thinking there are seperate issues here, one being a fuel related issue that's pissing away fuel, and one with the tune that's causing the hesitation.

as i said, it just seems all too weird that in one day, it's gone from no hesitation, hunting idle, to next day, full hesitation at the same load every time, perfect idle, and the monitor settings on my PFC have reset (possibly the whole PFC, i dont know how to check)

[nisskid]

Check your fuel voltages? something got to do with fuel cuz

how can i do this without a voltage tester? is it something the PFC can display?

[brother_david]

Have you checked the sparkplugs, every single one since one might be fine and the other bad, are they white/black, gooey? A good way to determine if its a fuel issue at all, would be white if its running lean.

Also i could imagine the stock lambda might be damaged, making it hesitate as it wont give the correct values to the ecu, making it run bad and sip more fuel?

[nisskid]

would that happen overnight though? it was running fine one day, smooth all the way to redline, albeit a hunting idle. then next day i go to turn the car on it's non-stop hesitating. it's like the issue manifested between the car dying the night before (ran out of petrol), me putting 10ltrs of fuel in from a jerry can, and then turning on the ignition. i thought about it possibly being a bad batch of fuel (or even possibly wrong fuel as the jerry can was filled up by some japanese dude, and i dont have a good enough grasp on japanese to notice what fuel he's putting in lol) , but id expect some knock or something?

once again it just seems too suss that its just a coincidence that the PFC monitor settings defaulted the same time. i had drunken mates in the car at the time, in fact 2 sitting on top of each other in the passenger seat, thinking maybe something was kicked and maybe a wire knocked loose or something.

[Tangles]

yep wire loose would reset the pfc.

installed my pfc this week to my rb26dett r32 sedan, but couldnt save (would reset) because a wire to the ecu pinout was faulty.

replaced a small section of 1 wire and all was fine.... had to flick wires a few times to find out which one was cutting on/off.

might want to start at the ecu wiring, flick each wire while engine running and see if you have a 'corroded' wire

weird, but age of these cars would suggest that its possible

as for sucking down fuel, yeh it could be the pfc / oxygen sensor / afm / plugs etc, try my above suggestion 1st,

also perhaps try to look for a pinhole fuel line leak?

fine at idle, but would spit out fuel once under enough pressure

good luck mate

[Adriano]

Could be a fuel leak from the pump inside the tank, seen this a few times

[nisskid]

yep wire loose would reset the pfc.

installed my pfc this week to my rb26dett r32 sedan, but couldnt save (would reset) because a wire to the ecu pinout was faulty.

replaced a small section of 1 wire and all was fine.... had to flick wires a few times to find out which one was cutting on/off.

might want to start at the ecu wiring, flick each wire while engine running and see if you have a 'corroded' wire

weird, but age of these cars would suggest that its possible

as for sucking down fuel, yeh it could be the pfc / oxygen sensor / afm / plugs etc, try my above suggestion 1st,

also perhaps try to look for a pinhole fuel line leak?

fine at idle, but would spit out fuel once under enough pressure

good luck mate

champ mate, will check tonight.

[paulr33]

do you have the boost control kit?

when the PFC is data init'd to defaults the boost kit is turned on by default

this means, if yours was "reset" and you aren't using the boost kit the engine check light would remain on until you disable the boost control kit

the PFC has no limp mode or back out mode other than what the stock ECU has

and this is your typical if AFM is dead, cap rev limit at 2500rpm etc - really basic rev cuts and idle protection

it wont know if your fuel pump is being gay or leaking fuel etc

[nisskid]

ok, so some news.

fuel pump went back in tonight, fuel tank was still pretty much where it was a few days ago, so ruling out a fuel tank leak (probably)

took it for a drive, same hesitation. had a search through the commander, found a AF setting, was set on R33 GTR (what looks to be the default). changed it to Z32 AFM (im running twin Z32's atm) and the hesitation stopped.

the car seemed to be running ok, except when i got to some hills and put my foot down a bit. car runs like dogs balls. so thinking it's definitely been reset, and running a shitty default map.

now, a few things, these are the max's i got, from putting my foot down once:

A/F: 5115

Ign-t: 20 idle

40 max

INJ-D: 96.5%

knock: 14

RPM: 4524

boost: +0.66kg/cm2

now as u can see, something's wrong, i was barely getting 75% inj duty before when running bout .9 bar, on redline, now im pretty much maxing injectors out with bugger all rpm, or boost.

i ran a sensor check, and this is what i came up with.

AF-1: 1.07

AF-2: 1.07

THRO: 0.46

BOST: 1.34

WTRT: 1.34

AIRT: 3.28

02-1: 1.44 (changes with revs)

02-2: 0.02 (doesnt change at all with revs)

Key: X=empty circle O=solid circle

IGN: O

STR: X

IDL: O

A/C: X

PWS: X

NTR: X

***: X

***: X

ECC: O

WRN: X

F/P: O

FP1: X

FP2: X

02H: O

ACR: O

FAN: O

the thing that caught my eye was the low voltage of the 2nd 02 sensor, i was thinking before, either it could be buggered, or im wondering if with the big single setup, they ditch one of the 02 sensors, then tell the powerFC this, and obviously the FC going back to default, it would be expecting 2.

i dunno, just a thought.

version of PFC is:

RB26DETT

Power FC

Ver8.04A

FC COMMANDER3

Ver5.01A