Car Leaning The F--k Out. Please Help Asap

[r33cruiser]

results= if your car is running lean, sluggish, wanting to stall or lacking power. change the o2 sensor. it may not look damaged but looks can be decieving, besides is ruining the mixture and possibly the engine worth $89?!?! i used a EL falcon sensor. it is a direct replacement with same circuit and 3 wire setup. simply crimp the similar wires up.

http://www.skylinesaustralia.com/forums/O2...sor-t43095.html

hi. i only have a narrow band afr gauge, but it still gives good warning. used to beat any mildly modded car out there of equal size. now.... dead :*(

after 1-2 hrs of driving the car will lean out. the only time that it actually moves from its dormant position is when the clutch is in, or when i let off the accellerator. now it hasnt happened for a long time since ive upgraded from 95ron to 98 ron. the car feels sluggish, lacking power and little response.

r33 gtst.

engine mods= 3" exhaust

no cat

shielded/boxed pod with cai

nismo fpr

bosch 040, with dedicated earth and power, to get full 12v

fmic with water spray

boost controller. at time of incident was set to 8PSI

i will be resetting the ecu tomorro. also i will be tinkering with the fuel pressure. what is the MAX pressure that the injectors can handle, and do i measure the reading at idle?

thanks in advance

i hope with your help, i get it back to the piece of pride and joy that it used to be. CHEERS GUYS

Edited December 2, 2007 by r33cruiser

[r32woohoo]

fuel pressure at idle should be 35-40psi i think.

it wouldn't do you any good playing with the fuel pressure with the std ecu anyway

im gonna take a stab at the fuel pump being the culprit. since it only happens after a couple of hours the pumps probably getting hotter and not working properly.

Theres been a few threads about the 040's going bad when it gets hot.

T04gtr had a thread about it and im pretty sure cubes and guilt-toy had one along the same lines too.

[UCD15R33]

does it feel like it shutters and misses and coughs and pops???

[r33cruiser]

it pops a bit in between gears. but it only coughs and splutters when u are rolling. eg when reverse parking etc.

if that is the fuel pump......makes sense. will have to have a look. the thing is IT HAS NEVER HAPPENED since i started using 98octane fuel?

anyway i will recheck all the usual culprits....fmic piping, connections, etc.

if all else fails will just borrow a mates 02 sensor and see what happens

thanks for the help guys.

most mechanics are like, r33 wtf is that?

Edited December 1, 2007 by r33cruiser

[UCD15R33]

Yeah maybe Also maybe needs a tune becasue of the fuel presure. mine did similar till i got a tune threw it i though it was fine. Also maybe fuel too. Doe it ping at all

[r33cruiser]

not audibly. but the lean warning went off, so i took it easy.

anyway guys i adjusted my fuel prs to 40psi at idle. it was originally at about 28psi. will take it for a run and see how it goes

[r33cruiser]

hey guys.. replaced my o2 sensor and it is all sweet. must have been that. replaced it with an el falcon o2 sensor.

thanks to the guys who helped me, and a shout out to sunnycoast for explaining how a new o2 sensor helped him.

for u guys. here is the pics of the old sensor.

was in pretty bad shape. any skyline owners nightmare

[sh@un]

as soon as i saw the thread title i was gunna suggest looking at the 02- this is the first thing to check in any car that has a closed loop lean cruise setup

[Bunta]

you only just started using 98 what were you using before that?

[r33cruiser]

95ron before. starting using 98 about 3 months ago.

thanks again to all the ppl that had suggestions

results from new sensor= actually can run rich, or to my liking. does not run lean anymore. car pulls and pulls and pulls, more responsive. i havent noticed more efficiency, but it may be my fuel pressure tho. car is smooth, does not stall, shudder or pop/die off on idle or gear changes

lol, admin u can close the thread now if u want

Edited December 2, 2007 by r33cruiser

[Mr_GaZZa]

hey mate,

you serious about this? i got same problem... runs lean as!!

pops when changing gears, surges/ spulters to make power and fuel gets used quick!! does it after a while of driving... and yeah i got a new bosch 040 fitted aswell!

[TTT]

why would he lie?

[Mr_GaZZa]

nissan told me they only last / work effiently up to 500hrs

=S

[TTT]

yes..

And Cat converters are only good for 40,000kms.

it's a part that sits 20cm from the exhaust side of the turbo..

800 odd degrees of heat, for 500hours..

I'm sure that's understandable.