3FE - how do they run w/o o2 sensors?

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If I understand correctly, the O2 sensors control the fuel/air mix. When the sensors fails or is removed the ECU uses a set fuel/air mix and can not adjust for changing engine performance / environment. So, it should run, but in a 'safe' or 'limp' mode since it can not regulate the changing needs of the engine.
Hope that helped.
Anybody got a better explanation, please?

I think Rob nailed it.

the computer should have a "limp home" mode. so when you disconnect the O2 sensor it goes into a mode that will run crappy but still run..
I would say yes, the computer really has no idea what the mixture is so at idle I would imagine it would run like crap..
It runs like crap without the O2 sensors. The idle is all over the place, and there is no real low end torque to speak of. The engine finally gets running decent in the middle rpms, but your dumping fuel the whole time.
You might do some research into putting a dummy load where the O2 sensors were. If you could figgure out what the ECU is looking for you could probably trick it. Another option is that if it runs rich you could modify the Air Flow Meter a bit to account change the fuel air mixture.
Mace said:
the computer should have a "limp home" mode.
It's not really a limp mode, but an "open loop" mode, which means the computer is not using feedback from the O2 sensor to manage the fuel/air ratio (which is set a 14.7:1, the most effiecient stochiometric ratio for use with the cat). The motor runs in open loop until it reaches normal operating temp, and sometimes at idle, or when the O2 sensor is dosconnected ;)

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