Lean codes and the Polar Vortex

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Bolt snapper

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Being right in the middle of the Midwest Polar Vortex this morning, I backed my Expedition ('04 5.4) out of the 38-degree garage and drove 5 miles to work. On the way, the Service Engine Soon light popped on with two lean codes - bank 1 and bank 2 (P0171 and I can't remember the one for bank 2). The air temperature was -14F, and the truck never did reach operating temperature the whole way to work.

I'm assuming this is no coincidence that the codes first appeared today with the unprecedented cold? More curious as to why this would result?
 

mquick5

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Only -5 here today, with a -30 degree wind chill. My passenger rear door is making a awful racket when opening and closing. But truck ran fine. My garage is 65 degrees, but it only houses the Mustang & quads.

Sent from my garage using Tapatalk
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