DTC P0171

[az'03Silverado]

I just changed my oil, oil filter, air filter and fuel filter. After this the truck sat for 4 days (while I was in Hawaii!) and on it's first drive this morning I get the SES light with the P0171 code. Any thoughts. I'm taking it in tomrrow for a check but I wanted to throw it out for opinions.

[camel]

bad o2 sensor on that side of the engine perhaps?

[az'03Silverado]

Just got back from the dealer. It was a clogged fuel injector rail. They flushed it, changed the filter (again) and reset the computer. So far, so good.