Well, I'll answer here instead of at benzworld, since you've explained better here...
Giving the P0132 is a token of that the voltage on the sensor is permanently
high. High voltage, indicates a rich running engine. Changing out the sensor
will not mend that. Its merely showing what its happening. That fits your horrible gas
milage also. And since you know what you did when this occurred, rewire the MAF, well
that would be prime suspect... The MAF might give slightly off reading, at least
not wildly wrong, that would give a rich condition, that is the O2 sensor task
to discover. Your O2 may now be so full of carbon, that the other condition P1131
turns up.
Read about sensor here;
http://www.gnttype.org/techarea/ecmsensors/O2sensors.html
Other things it could be, wrong timing, leaky fuel pressure regulator.
br,
syljua