Failed smog test

My 2003 Ford Explorer failed the smog test and the failure description are the following:

Too lean: Bank1

Too lean: Bank2

Thanks in advance

This “failure” was because your check engine light is on, right?

No, the check engine light was not on

Did they test the car on rollers and sample the tailpipe emissions? What state are you in?

I’m in California, and yes on rollers

I’m just going to take a shot in the dark…Check carefully for any air leaks between the air filter and the throttle body. Check for air leaks ANYWHERE. clean the MAS, the airflow sensor just down-stream from the air filter. Add a can of Techron to the fuel tank.

Did it fail at idle or at higher speed, what exactly does the failure report say?

Too lean: Bank1
Too lean: Bank2

That was all the report said. Thank you very much.

There is more information about how your vehicle performed on that emissions test report. There is more than just the “Failed” part. Let us have that information, if you really want advice on how to fix it.

The too lean messages were pulled from your cars computer and are not the result of test readings…Usually, when the computer detects an emissions problem it triggers the CEL. If the CEL is not on, I’m very surprised you failed the test. You might have Autozone read the codes (for free) and then clear them and then have your car re-tested.

disconnect the battery overnight & go to a dif. but in ground test station.
Ca is a con job.
Read about it at web site & other smog stuf too.