Does having a bad o2 effect the way a car drives? What are effects of a bad o2. My car is a 95 and and has a code for a bad o2 but the car feels ike it is bogging at 2000-3000 rpm , i thought on a obd1 car the o2 has no effect. What happens to the car when it goes in limp mode. Thanks

 

"Limp mode" will have nothing to do with your issue. If the PCM loses input to various sensors, it simply substitutes assumed values to keep the engine running.

It would stand to reason that if you have a code for the O2 and your car is running poorly that perhaps it should be fixed. All f-cars require O2s for fuel trim. OBDII cars have rear O2s only to confirm that the cats are working.

 

Without fueling feedback from (both) o2 sensors, the car will stay in open loop fueling mode. Fuel consumtion will go up by about 10% and could even be dangerous.