How fast should o2s switch
So my question is, are the o2s suposed to act this way when the engine is running rich or are they lazy and not switching fast enough and need to be replaced?
From what Ive read they should fluctuate from 200-800mv rapidly if they dont the sensor is going bad.
So if the engine was actualy running rich and the o2s where ok wouldn't the sensors read something like 300-900mv switching rapidly?
Make sure its in CL, and if it is, the sensors are probably going/gone bad.
the o2s could be telling you the truth though its rich. are the fuel trims pulling fuel?
have a look at the fuel pressure regulator and check fuel pressure. if you are still running an egr they can coke up a thottle body enough to cause rich codes.
is this the forced air truck in your sig? the afr is richer on those. i have never tuned a forced air engine but would not the parameters for setting the rich codes be out to lunch?
the o2s could be telling you the truth though its rich. are the fuel trims pulling fuel?
have a look at the fuel pressure regulator and check fuel pressure. if you are still running an egr they can coke up a thottle body enough to cause rich codes.
is this the forced air truck in your sig? the afr is richer on those. i have never tuned a forced air engine but would not the parameters for setting the rich codes be out to lunch?


