starting point for tuning an ls2 auto

[SV8346]

can some one point me in the right direction for starting to tune an ls2 using the standard o2 sensors.

A mate has asked me to try and help him with his fuel economy as he is getting roughly 250-300ks from a 70ltr tank of fuel. He is not after any performance gains as it already goes well enough for him, he mainly wants to try to increase his fuel economy. The operating system he is using is 12598977 from an 05 model HSV clubsport.

I am so far only familiar with using the COS 01290003 which uses grams/cyl for the VE table and has commanded fuel vs RPM.

[dfe1]

Except for ECMs like the E38 that have operating systems that don't incorporate and actual VE table, all the operating systems operate pretty much the same way with respect to VE. The actual units in which VE is displayed can be selected by clicking "Edit" and "Properties".

I don't think you'll pick up much fuel economy by working the VE table (actual or virtual), because the system is going to attempt to maintain stoichiometric. (the only exception would be if the VE table is so far off that required correction is beyond system limits.) You'll either have to change commanded stoichiometric or switch to a COS and run semi-closed loop. You'll probably find it easier to improve fuel economy by working with timing, and DFCO.

[SV8346]

allot of the stft and ltft are going along way into the "-". It sayis in the description for map B0200(Main VE Table) that when the MAF is functioning correctly this table is used to "verify" the MAF readings, if the MAF has failed(or if disconnected) then the VE table will be used to predict the engine airflow.

Is there a way within the program to turn off the MAF so it doesnt look for it at all, I know the dtc's can be turned off but is there anyway to turn it off within the prg so it doesnt look for it at all, The MAF cant be unplugged as it also has the IAT sensor built into it.

[hquick]

Can you not install a standalone IAT sensor. There's a harness available which turns the 5 wire MAF/IAT into seperate plugs for seperate MAF/IAT setups.

[Doc]

Set the following DTC Enablers P101, P102 and, P103 to "one trip."

Set C0301, C0302, C0303 to "1."

Viola, you are in SD.

I agree with dfe1 about changing spark and commanded fueling for the savings you seek.

[SV8346]

thanks doc, i'll give it a go

[SV8346]

Can you not install a standalone IAT sensor. There's a harness available which turns the 5 wire MAF/IAT into separate plugs for separate MAF/IAT setups.

yeah was thinking this exact same thing, i have found another website that says that the Brown/yellow and solid brown wires are for the IAT and the rest are for the MAF. For now what i'll try is to unplug the remaining wires from the harness so it doesn't look for the MAF.