2002 mercury sable wagon
So i got this sable a few weeks ago, and the check
engine light was on so i had it scanned
P1000
P0301
P0302
P0316
So i changed the plugs and wires since it gave me
a misfire on 1&2 and random misfire on start up,
well after that i cleared all the codes, took it for a
drive and the light came on and started blinking i
scanned it again with the following
P0136 o2 bank 1 sensor 2
P1400 dpfe sens circuit low volt
P1131lack of heated o2 sensor bank 1 sensor 1
switch indicates lean
P1151bank 1 sens 2 switch point indicates lean
P0301
P0302
P0303
P0316 misfire on startup
What am i doing wrong here as some of the codes
did not pop up when i ran it the first time, and i did
one plug/ wire at a time not to be confused and
replaced the 6 plenum gaskets as well