Anybody know where I should start with this code?

First place I'd look is the air cleaner box, is it sealed so the only air comes thru the intake?

Anybody know where I should start with this code?
??????
It may help us to help you if you can tell us something about the 'car',
Year, model, engine size, type of fuel injection, driveablity problems etc.

It was a dumb mistake that caused it.
I unplugged the connector to the air filter box.
After plugging it back in, the engine light eventually went off.

It was a dumb mistake that caused it.
I unplugged the connector to the air filter box.
After plugging it back in, the engine light eventually went off.

Well that other poster was close. Thanks for checkin back and telling us.