My 97 f250 is showing engine code 'lean bank one and two'. I have read many posts on the very same codes showing with others and found it very useful. Here's the rub for me however. Virtually all the posts I've read all involved a rough running engine accompanying these codes. My truck runs like a top, idles beautifully and no noticeable loss of power or hesitation etc. Can anyone explain why I have had this code for almost a year without the engine showing any crankiness. I've deleted the code a few times but it always seems to return. What gives? I would love to know which of the possible causes; ( intake gasket, MAF,o2 censor, PCV elbow or grommet, etc) is likely the culprit?
Anxious to hear all of your inputs.

 

You've pretty much stated them all. Add fuel filter to the mix. You're either getting too much air, not enough fuel, or the sensors are incorrect.

 

I had the same thing go on with mine and never really had a problem until it just started idling rough on me. turns out the elbow on the passenger side cover had cracked around the base and was letting air in. I checked this using carb and choke cleaner on a number of my vacuum hoses until i found it.

 

So your engine code showed lean both banks and your vehicle ran perfectly I'm the beginning like mine is? Mine has gone almost a year with the code and still purrs like a kitten.

 

Check the maf sensor for contamination.

 

I'm beginning to think its something else. Even when I'm in gear it acts like it wants to choke down. Its doesn't do this but every once in a while so I'm kind of at a loss now