I Installed a DC3 catch can and about 50 miles afterwards my engine threw a P0171=system too lean bank 1. The only reason i can think of for this happening is that i may not have tightened down the drain on the can that connects the valve cover vent and the intake all the way allowing some air to enter after the airflow sensor. Does this sound right?

 

Anyone?

 

No.

 

So it could just be a coincidence?

 

Your O2 sensor is bad.. the front one. I had that stupid cel for awhile until I replaced the front O2 sensor. Although, cant' rule out you might have messed with something else.

 

Think I fixed the problem, the valve wasn't fully closed. I closed it and tested the valve with water