I gutta question or two:

Is it an 04 S-10 with a 4.3 or maybe an '03? I looked here:

[...] [[...]]

and found no such animal.

Then I found 4.3 S-10s in '03 and read about P0442. Interesting that it says a P0442 will set if "Refueling Rationality test is... Login to read more.