busta9876
11-20-2013, 05:59 AM
There was a thread about this subject back on Monodax. I was looking for information on the use of single bank fuel control. I was messing around with it this spring and never could get it to work like I 'Though' it should work. I'm using OBD2 Tuner Cat as well as HP Tuners custom 2 bar.
5.3L with two narrow band sensors wired as factory, wide band wired into HP Tuners aux input.
My situation is this: 5.3L Vortec, single turbo setup, both banks merge before the turbo, and single down pipe. The turbo is very close to the exit of the passenger side, so no room for an o2 sensor at this location to be able to only sample exhaust from that bank. So I opted to just control all 8 with a single o2 sensor. I accomplished this by setting the injector bank assignment of all 8 injectors to bank 1. I disable all diagnostics dealing with Bank 2, Sensor 1 and 2. What I found, is the PCM would never go into closed loop by its self, I had to use HP Tuners to force CLOSED loop and it would do it as long as I was forcing it.
Long story short, I had to have both narrow band sensors physically installed in the exhaust stream. The PCM would wait to see both sensors activity increase (indicating heated up sensor) before allowing closed loop, even though it only adjused fuel based on settings from Bank 1 Sensor. The LT ans ST fuel trim for bank 2 would usually MAX out one direction or the other, however, since fuel injectors were all tied to bank1 , fueling stayed correct. I also had to disable rich and lean diagnostics for bank 2.
So I have achieved 'single bank' fuel control, but still MUST have the bank 2 sensor installed and it must report activity for PCM to go into closed loop. It seems the check box 'single bank fuel control' had no difference.
Anyone else messed with this any?
5.3L with two narrow band sensors wired as factory, wide band wired into HP Tuners aux input.
My situation is this: 5.3L Vortec, single turbo setup, both banks merge before the turbo, and single down pipe. The turbo is very close to the exit of the passenger side, so no room for an o2 sensor at this location to be able to only sample exhaust from that bank. So I opted to just control all 8 with a single o2 sensor. I accomplished this by setting the injector bank assignment of all 8 injectors to bank 1. I disable all diagnostics dealing with Bank 2, Sensor 1 and 2. What I found, is the PCM would never go into closed loop by its self, I had to use HP Tuners to force CLOSED loop and it would do it as long as I was forcing it.
Long story short, I had to have both narrow band sensors physically installed in the exhaust stream. The PCM would wait to see both sensors activity increase (indicating heated up sensor) before allowing closed loop, even though it only adjused fuel based on settings from Bank 1 Sensor. The LT ans ST fuel trim for bank 2 would usually MAX out one direction or the other, however, since fuel injectors were all tied to bank1 , fueling stayed correct. I also had to disable rich and lean diagnostics for bank 2.
So I have achieved 'single bank' fuel control, but still MUST have the bank 2 sensor installed and it must report activity for PCM to go into closed loop. It seems the check box 'single bank fuel control' had no difference.
Anyone else messed with this any?