so i keep getting a CEL for my o2 sensor on my obd1 ls motor (91), and ive noticed my car is runnign like shit. response is poor, power still seems good its just that its doesnt respond very well. a few questions..

would a bad 02 sensor cause this poor performance (i recently did a full tuneup so its none of that)? when the CEL comes on for it does it put my car into limp mode or somethign like that...?

do those o2simulators affect the performance of the car? do they just get rid of the CEL or do they really pretend like the o2 sensor is detecting the correct amount of air..or whatever it does?

i heard somethign about a resistor and a capacitator to trick it into thinking the o2 sensor is ok...anyone know what this is?

o and my gas mileage sucks ass right now too.