o2 sensors

[pchad1972]

04 silverado 5.3 liter , what are the p codes or numbers to just shut off the two rear ones after the cats or where the cats used to be ?

[06MonteSS]

you have an older revision 7193? still on a 2.xx revision??? or is it on a newer 9rXX revision? the newer 9rXX revisions can not disable codes, you'd have to get a custom tune made...

if it's an older 2.xx revision, then when you go into Modify Tune, there should be a menu option for OBD... go in there and disable the O2 codes, the CAT codes, and you can also disable the COT protection by setting the COT temp all the way up as high as it will go...

[pchad1972]

i have the older version i can turn off my o2s yes and my cot , but some times it says bank2 sensor 2 low voltage , does that usually mean a bad o2 sensor. i have no cats but i turned my o2s back on since im running e-85 so far so good my ltft are at -1% cruising at 70 mph for about 20 miles and my afr are at 10% i put a wide band afr in my truck with a guage in the pillar post stays in the yellow and green when cruising down the road and all the way in the green at wot. i put in another sensor just for that did not come off one of the others. so i know its got to be a good reading and put in a electric fuel pressure guage all by autometer on a pillar post and fuel pressure is at a consitent 61 psi goes down to 59 for a spilt second at wot. but can i use my 87 tune for 93 octan and use my 93 for my e-85 adjustments and adjust my 87 for 93 timing wot fuel and all that stuff ? so once i adjust 87 for 93 my adjustments wont be messed with i can have two set ups for both kind of fuels without alwaays messing with the adjustments once set always set ?

[06MonteSS]

once you get your injector slope setting correct, you can just use the same setting for the other tune you install...

fuel octane has nothing to do with how much fuel gets sprayed by the injectors... so whatever you dialed in your fueling with the injector slope for the 91/93 tune, you can use the same injector slope setting with the 87 tune when you install it...

[zz50]

Are you running E85? If so then your AFR meter should be adjusted to reflect the true stoichiometric number which is is 9.85% vs 14.64% for gasoline and WOT is .86 times that or 8.47% to shoot for. If your AFR meter is adjustable for lambda that is the equvalent value.

[pchad1972]

im running about 9.50% on my afr guage and have my ltft at about -1.00 % so far running pretty good picked up some hp , but i also fully enclosed my air raid filter made a box , and have a 4 inch hose that feeds from the bottom , then ran hose under the froint spoiler, made the box out of plexiglass sealed with clear silicon, that helped out alot but then had to readjust my ltft's again because of all the added air , had to go buy bigger enjectors stock ones could not supply enough fuel. that forced induction really does work.