Hey All,

Picking up a P0420 code lately.  With only 62,000 miles on the OD I'm
not ready to have a catalytic converter replaced.  Checking the fuel
trim, I have about 20 frames of live data I picked up with my ODB2
scanner.  The truck was at operating temperature after my evening
commute and I held the RPMs up to 2500 to collect the data.

The data tells an interesting story.  Seems like STFT B1 is much
richer than STFT B2 and LTFT B1 is leaner than LTFT B2.

STFT B1:
2.34 5.47 7.03 3.13 3.91 3.91 8.59 3.91 3.13 6.25 6.25 6.25 2.34 5.47
3.13 6.25 6.25 2.34 5.47 2.34

LTFT B1:
7.03 7.03 7.03 7.03 7.03 6.25 6.25 6.25 6.25 6.25 6.25 6.25 6.25 6.25
6.25 6.25 6.25 6.25 6.25 6.25

STFT B2:
-3.13 -2.34 -1.56 -1.56 -4.69 -5.47 -5.47 -5.47 -1.56 -2.34 -6.25
-2.34 -3.13 -6.25 -5.47 -6.25 -6.25 -1.56 -3.13 -5.47

LTFT B2:
10.94 10.94 10.94 10.16 10.16 10.16 10.16 10.16 10.16 10.16 10.16
10.16 10.16 10.16 10.16 10.16 10.16 10.16 10.16 10.16

Last December I had about eight gallons of bad fuel in the tank which
cause the truck to misfire and immediately stall, the fuel was that
bad.  Had that taken care of at a dealer, and they said that my
injectors and fuel pump might go bad from the fuel I put in there.
Fuel pressure looks Ok, but wondering about the injectors.  I put a
can of sea foam into about a 1/4 tank of gas to try and clean the
injectors.

Regarding the fuel, my bad.  I had eight gallons of fuel from last
summer, was only about six months old and I used stabilizer in it.
But I think the 5 gal plastic tanks were old enough that they let the
fuel oxidize anyway.  Stupid me for not checking it before I put it in
the truck!!!

Thanks in advance for any tips on this!