Yesterday I got the runner re-aligned after new lift and tires. The shop disconnected the battery to do the work. Not sure why they did so, probably just standard procedure. I know they disconnected the battery because my driver side window didn't work properly. I got home, disconnected the battery again, reset the automatic windows, and took off to a friends house.
Today I get in, give it the normal warm up, and head off. I noticed the idle was very low, less than 500 rpms. About a mile down the road, the CEL and accompanying dash lights turn on.
Bring it in to Advanced Auto Parts to do the code search. He tells me P0101, mass air flow circuit 1 something or other.
I have had the rpms run low after reconnecting battery before, but they always go back to normal after a while.
I guessed that I didn't perform the proper post battery connection operations, and just drove off, thinking that everything would work out.
Came home from the code finder store, disconnected the battery, waited 10-20 minutes, reconnect battery, turn on and let idle for 5-10 minutes, then drive around for a little while.
The rpms are back at normal operating speed, and the CEL is gone.
So, if anyone happens to get a P0101 code after they had their battery disconnected, try this! It might just work for you.