My 07 Outlander keeps having intermittant "service engine soon" lights, which go away after 3 heat cycles, but come back again in a few days. When I have read he OBD codes, they are saying lean condition on fuel rail 2. I've tried running injector cleaner to no avail.

Any common caused for P0171 - P0174 codes, before I go in and change oxy sensors? Common vacuum leaks, etc. on these vehicles?

 

Fuel trim too lean on both side P0171 & P0174 point normally to Oxygen sensor.

But I would check for air leak after the Mas Flow sensor and/or at least inspect the MFS for dirt this could make it less responsive.

 

OK, I'll check the MAF, thanks. So, the upsteam oxy sensor is likely the culprit, you think?

 

Funny, I just saw this problem fixed on a corvette on SpeedTV 2 weeks ago and it was the O2 sensor.

This would explain why both sides are lean.

Aren't you still covered by the Emission warranty? If yes, check with the dealer as this is an emission problem.