irratic idle

[wjkiic]

I changed the spark plugs on my 2004 ford expedition (123000 miles) which was a lot easier than i thought. I noticed the tube connecting to the PCV valve was disconnected I replaced the hose with a different hose but the new hose was straight and bend was tight. After the second day of driving the check engine light came on I had the codes read and i got P0171 and P0174 I cleared the codes and replaced the hose with a longer one that curved easier. now I have codes p2195 and p2197 and my car idles at about 500 rpms and sounds like the engine is going to die. Any suggestions on where I should start.

 

[bedrck46]

P2195 - Lack of HO2S-11 Switch, Sensor Indicates Lean
P2197 - Lack of HO2S-21 Switch, Sensor Indicates Lean

Possible Causes

Electrical:
Short to VPWR in the harness or HO2S.
Water in the harness connector.
Open/shorted HO2S circuit.
Corrosion or poor mating terminals and wiring.
Damaged HO2S.
Damaged PCM.
Fuel System:
Excessive fuel pressure.
Leaking/contaminated fuel injectors.
Leaking fuel pressure regulator.
Low fuel pressure or running out of fuel.
Vapor recovery system.
Induction System:
Air leaks after the MAF.
Vacuum Leaks.
PCV system.
Improperly seated engine oil dipstick.
EGR System:
Leaking gasket.
Stuck EGR valve.
Leaking diaphragm or EVR.
Base Engine:
Oil overfill.
Cam Timing.
Cylinder compression.
Exhaust leaks before or near the HO2S(s).