Dangers of Running Rich, 3sgte owners Options

[jgreening]

Well, ten days into ownership of the 3sgte and I can safely confirm what everyone else has said over and over....these engines run very rich. I have read many posts about this and about the fact that Toyota made it this way to avoid lean conditions. However, I would imagine that running an overly rich condition cannot be good for the engine over time either. I am wondering whether for engine longevity and reliability purposes, us 3sgte owners should take action either through an S-AFC or stand alone to lean out the A/F ratio. Obviously, we can see some horsepower gains from doing so but I am particularly interested in responses dealing with engine life.

[Kwanza26]

Running a bit rich doesn't hurt the engine. It'll eat away at your cat (if you have one) and your O2... but it's a LOT safer than running a bit lean. Running rich has little to do with the fuel pump, although running lean does. It's more than likely the ECU, AFM, TPS, O2, or something between those sensors.