Vortec 5.3/6.0/LS Single Bank Fuel Control Option

[1project2many]

I haven't messed with it. But I'm curious about your setup. Do you have a "dual exhaust" option? Is it still checked?

[busta9876]

I've only seen the 'dual exhaust' option box on the black box vortec PCM's. On the 2002 5.3L calibration the option is actually called "Two Bank Fuel Control Option" The default value for this has an X in the box. Its under Calibration options in TunerCAT OBDII.

[EagleMark]

I had some split fuel trims and tried the "Two Bank Fuel Control Option" and had no effect on bank to bank fueling. Now this was on a 98 Vortec to 0411 PCM swap so not actual LS engine. Never have tried on LS engine. Nor did I try the Injector Asssignment.

Also removing all DTCs for post Cat 02 sensors had no effect and they had to be physically disabled to work.

I wonder if you disabled Readiness test on O2 sensors when trying one sensor?

[TunasTwins]

Have you thought about simulating the output to both O2 sensors via one WB sensor? Some people seem to have luck with the simulation but I dont know if its truly proven for everyday use

[Caleditor]

I have use it many times. If it is a turbo application it will allow you to mount both O2's in a single pipe with no ill effects.

I had a car a few years back that when I had 2 bank fuel control turned off the fuel trims were close. I converted it to a 2 bar OS and they would be split again. I figured it had something to do with the COS.

I found on a bunch of cars it does not work like I expect it would. I found in a very few it does. I have gone over the calibrations in hex and found a few settings that may make it work, but I have not done further testing
If the sensors are in 1 pipe it fixes the fuel trims.

[EyesofThunder]

Was experimenting with the Dual Bank/Single Bank on my L29 454 today, no worky (I know, I have a dead right bank O2). But looking at the L30 (the 305), it is factory single bank and works (obviously or GM wouldn't have shipped it), but it also has 3rd O2 sensor checked too. I will experiment more tomorrow on it.

The other question is did GM do something like ground out the Bank 2 sensor input?

[Hog]

Was experimenting with the Dual Bank/Single Bank on my L29 454 today, no worky (I know, I have a dead right bank O2). But looking at the L30 (the 305), it is factory single bank and works (obviously or GM wouldn't have shipped it), but it also has 3rd O2 sensor checked too. I will experiment more tomorrow on it.

The other question is did GM do something like ground out the Bank 2 sensor input?

Yes the Vortec 305 has that 3rd precat O2 sensor and the single aftercat O2 sensor.
The L31 350 and L29/21 454 uses the dual precat and dual aftercat sensors.

peace
Hog