Cool weather brings on P0171 bank one lean

[Yukon98]

Maybe try a hotter thermostat if it seems to be temperature related? 180 I believe is oe. I run a 190 here up north all year. I know people in Alberta switch theirs out between summer and winter but their temps are more extreme. My truck is finicky with the intake air temp, likes to throw codes in the summer and less so in winter.

 

[df2x4]

180 I believe is oe.

Close but it's actually 195.

 

[ChrsLytn]

Pump is about 3 years old. It was from Chev.

 

[ChrsLytn]

It's got a 195 in it.