Question I recently caught a P1110 obd2 code (thank you AutoZone) on my 2001 9-5 base w/2.3 auto, 120K. An internet search has defined this fault as. Atmospheric Pressure Sensor Low Input. I have also found differing opinions on just what this really means. These are:
Bad O2 sensor.
Bad Bypass Valve or Dump Valve on the turbo plumbing.
Just a loose vacuum line.
Answer CK FOR ANY LOOSE VACUUM HOSES IF OK THEN THE CHARGE AIR BYPASS VALVE IS THE PROBLEM
Answer My problem was the turbo bypass valve. I replaced OEM Bosch unit with a Forge aftermarket valve. It works great, and feels a touch more responsive (not to mention being able to pass the state emissions test).