Fuel Trims

General Tuning Questions And Discussions
Post Reply
DeathSammich
Posts: 18
Joined: Mon Feb 05, 2018 8:18 pm
cars: VT Commodore

Fuel Trims

Post by DeathSammich »

I have an NVRAM but am having some issues. My main concern is i have no STFT on my right bank. I have the left o2 disabled for the wideband and my wideband afr seems good but my right hand o2 sensor has a LTFT of 12 but STFT is 0. The o2 sensor hangs in the rich zone or the lean zone for extended periods of time it doesnt go up and down like it should. Ive tried 2 o2 sensors with same outcome.

Second DFCO wont work and its enabled
Charlescrown
Posts: 1831
Joined: Sat Aug 06, 2011 7:58 am
cars: V8 VR Commodore BT1
LB Lancer 2L turbo & Delco
Starion TBI with Delco
Mitsubishi Lancer EVO4 track car
NA MX5
3 vintage motor bikes
Location: Padstow NSW

Re: Fuel Trims

Post by Charlescrown »

What car are you doing? I know the VR (I think) had a ECU earthing problem and made one sensor go lazy and it can be fixed by adding a good earth to the sensor.
immortality
Posts: 3416
Joined: Thu Apr 09, 2009 12:31 pm
cars: VH, VN, VS, VX

Re: Fuel Trims

Post by immortality »

OP, Can you please post a complete rundown of engine mods, problems and fixes done so far as there is a fair history here which I think will be relevant.

Charlescrown wrote:What car are you doing? I know the VR (I think) had a ECU earthing problem and made one sensor go lazy and it can be fixed by adding a good earth to the sensor.
That was the VS ecotec I believe.
DeathSammich
Posts: 18
Joined: Mon Feb 05, 2018 8:18 pm
cars: VT Commodore

Re: Fuel Trims

Post by DeathSammich »

Its a VT, i have an NVRAM, ive disabled left o2 and fitted a wideband. Mods are pacemaker extractors, dual redback cats into single 2.5" cat back, mace CAI, forged rods and pistons. Havent gotten to big mods yet as im still fixing some issues as you might tell lol.
DeathSammich
Posts: 18
Joined: Mon Feb 05, 2018 8:18 pm
cars: VT Commodore

Re: Fuel Trims

Post by DeathSammich »

Can pacemaker extractors cause issues with the o2 sensors?
User avatar
vlad01
Posts: 7780
Joined: Mon Oct 08, 2012 6:41 pm
cars: VP I S
VP I executive
VP II executive
VP II executive #2
VR II executive
Location: Kyneton, Vic

Re: Fuel Trims

Post by vlad01 »

Charlescrown wrote:What car are you doing? I know the VR (I think) had a ECU earthing problem and made one sensor go lazy and it can be fixed by adding a good earth to the sensor.
It was VS and maybe VT? that had the issue, VR run a much different earthing system and also only run a single sensor.
I'm the director of VSH (Vlad's Spec Holden), because HSV were doing it ass about.
immortality
Posts: 3416
Joined: Thu Apr 09, 2009 12:31 pm
cars: VH, VN, VS, VX

Re: Fuel Trims

Post by immortality »

IT's probably better to get a new bung welded in for the WBO2 and leave both the factory O2 sensors in place so they can do their thing. Check your logs to see if the engine is actually going into closed loop mode which I suspect it's not considering one sensor isn't fitted.
Wade
Posts: 562
Joined: Mon Jul 11, 2016 6:29 am
cars: Vr 5.0 statesman vr exec 5.0 turbo vy clubsport

Re: Fuel Trims

Post by Wade »

That you Christopher? If it is than yes, this car has more issues than my ex lol. You’ll need to let everyone know about what mods are done, what other issues it has and posting some good data logs will make it easier for the guys to help you out. Cheers wade
Post Reply