DTC P0153: 2/1 O2 Sensor Slow Response: Description
WARNING: This page is about a different car, the 2000 Dodge Intrepid, 2000 Chrysler LHS, 2000 Chrysler Intrepid, 2000 Chrysler Concorde, and 2000 Chrysler 300M. However, it is still accessible from the selected car via links, so may be relevant.
2/1 Heated Oxygen Sensor (HO2S) voltage is monitored with engine coolant temperature more than 147°F (64°C), after reaching a vehicle speed of 10 MPH, and throttle remains open (off idle) for 2 minutes and subsequently bringing vehicle to a stop and allowing engine to idle in Drive. DTC will set in Powertrain Control Module (PCM) memory when PCM senses 2/1 HO2S voltage is switching from less than .27 volt to more than .62 volt and back less times than required. Possible causes for DTC to set are: engine mechanical problem, exhaust leak, defective 2/1 HO2S, defective connectors or defective wiring.