Should I disable FAOSC?

[Hubes]

97 mustang gt, original h pipe is gone, aftermarket x pipe has 2 universal magnaflow cats instead of the original 6. Will FAOSC still function correctly, or should I turn it off? Thanks

[Adammm57]

They probably wont work and will possibly report a low catalyst function code. People I know have disabled it and it really hasn't affected them. It just disables LTFTs and nothing else really. Do with that information as you please.

[Hubes]

They haven't thrown a code yet, and they've been there for a couple years. But now that I'm thinking about it, it didn't have the light on when I bought it with no cats. It must be turned off in the tune, but hpt doesn't have the list of dtcs for me to turn off like with the gm stuff. Car came with an sct handheld tuner.

Anyway, I kind of like the idea of the faosc IF it functioned correctly, but I have my doubts it will with the aftermarket cats. My understanding was that it doesn't really change the ltft per se, but it kind of is a sanity check for the front O2s, and so then the eec will adjust the ltft accordingly