1jz running lean underboost?

[wolf31685]

ok so i plan on getting a wideband o2 for now i have a narrow band now when i'm idling or under light throttle it say its running rich when i step on it it says its lean but i doesn't smell like its lean what else can i do to rememdy this problem or do i have the narrow band possibly hooked up wrong the signal wire is connected to the blue wire on the o2 sensor on the y pipe

 

[pnutcar]

What do you have done to the car? If you've got stock turbos, stock inj, and stock fuel, there is NO WAY IN HELL that you're going to be lean. Your narrow band won't cut it, just get the wide band and know for sure.

I've been running the aem uego for over a yr now and LOVE it. Super easy and accurate.

 

[tlo86]

isnt the 1jz fuel pump better or something?

 

[pnutcar]

isnt the 1jz fuel pump better or something?

Its the same pump as 7m. The ONLY change for 1jz cars are the engines.

 

[tlo86]

Its the same pump as 7m. The ONLY change for 1jz cars are the engines.

must be thinking of the 2jz pumps vs the m

 

[pnutcar]

must be thinking of the 2jz pumps vs the m

The 2J denso pumps are way better than the 7m pumps, also flow more than walbros. Much quieter, reliable, and expensive too.

That still wouldn't make him lean. I'm betting its a faulty gauge. Wideband ftw.

 

[tlo86]

The 2J denso pumps are way better than the 7m pumps, also flow more than walbros. Much quieter, reliable, and expensive too.

That still wouldn't make him lean. I'm betting its a faulty gauge. Wideband ftw.

anyone put a 2j pump in instead of the walbro?

 

[pnutcar]

anyone put a 2j pump in instead of the walbro?

Seriously? I'm not sure about this site because I just recently started coming here, but this has been beat to death and then some on SF. Densos are much better pumps, but you can buy almost 3 Walbros for the price of a Denso.

 

[tlo86]

Seriously? I'm not sure about this site because I just recently started coming here, but this has been beat to death and then some on SF. Densos are much better pumps, but you can buy almost 3 Walbros for the price of a Denso.

meh figured id ask, im going for an a1000

 

[wolf31685]

3 inch exhaust from the turbo back and a front mount intercooler with 2.5 piping

What do you have done to the car? If you've got stock turbos, stock inj, and stock fuel, there is NO WAY IN HELL that you're going to be lean. Your narrow band won't cut it, just get the wide band and know for sure.

I've been running the aem uego for over a yr now and LOVE it. Super easy and accurate.

 

[apexi287]

A narrowband isnt going to tell you anything its just a light show get a wideband and come back. At cruise and idle it should be lean around 13.5-14.5 thats about around where i have mine, now if you have the same issue as me and made an unexpected amount of power on the stock fuel system youll need to upgrade i was running lean around 13.5 at wot with stock fuel system full exhaust and fmic at 16psi. I just put in 440cc and im running around 11.5 all the way to 10 untuned.

One other thing you may want to look at is your fuel filter when i did my walbro i realized the fuel filter so tucked behind the tank and had never been changed, that also could of been a major cause of the leaning out at wot, brown gas came out of the filter.

 

[tlo86]

A narrowband isnt going to tell you anything its just a light show get a wideband and come back. At cruise and idle it should be lean around 13.5-14.5 thats about around where i have mine, now if you have the same issue as me and made an unexpected amount of power on the stock fuel system youll need to upgrade i was running lean around 13.5 at wot with stock fuel system full exhaust and fmic at 16psi. I just put in 440cc and im running around 11.5 all the way to 10 untuned.

One other thing you may want to look at is your fuel filter when i did my walbro i realized the fuel filter so tucked behind the tank and had never been changed, that also could of been a major cause of the leaning out at wot, brown gas came out of the filter.

yeah those are often neglected and so cheap to replace lol

 

[apexi287]

yeah those are often neglected and so cheap to replace lol

yeah cost me like $10.

 

[wolf31685]

yea she seems to be runnign right now i dunno what it was but now she's idlin a little high at 1400 i'm gonna pull off the iac and inspect it possibly needs to be cleaned or replaced

 

[str8_6]

i would get a wideband with with data log capability. i love my aem uego, but it cant do that, so its harder to tune by yourself.

how much boost are you running? you should get at least an safcii/wideband o2. i was still subtracting fuel from my safcii at 348rwhp on stock injectors and mkiii turbo fuel pump so you just need something to control/monitor it.

as far as the fuel pump goes, you can buy used 2jzgte fuel pump for less then $100.00 and have it tested to see its output. with a kenne bell bap it can handle over 500hp. i'm running around 400hp with the denso mkiv turbo pump used..untested and doing awesome.

 

[OneJSupra]

i would get a wideband with with data log capability. i love my aem uego, but it cant do that, so its harder to tune by yourself.

how much boost are you running? you should get at least an safcii/wideband o2. i was still subtracting fuel from my safcii at 348rwhp on stock injectors and mkiii turbo fuel pump so you just need something to control/monitor it.

just curious how much fuel did you pull with the stock injectors at 348rwhp?