P1195moderate severityPowertrain
O2 Sensor 1/1 Slow During Catalytic Monitor
on 1997 Jeep Wrangler 4.0L I6 · 4WD
What this code means
The PCM has detected that the upstream oxygen sensor on Bank 1 is responding too slowly during the catalytic converter efficiency monitor. The sensor switching rate is below the threshold needed for accurate catalyst monitoring.
Symptoms
- Check Engine Light
- Failed emissions test
- Slightly reduced fuel economy
- Possible rough idle
Common causes
- Aging or contaminated upstream O2 sensor
- Exhaust leak near the O2 sensor
- Wiring issue causing signal delay
- Fuel contamination affecting sensor response
- Catalytic converter deterioration affecting sensor readings
Diagnostic steps
- Monitor O2 sensor switching frequency on scan tool (should switch rapidly at steady cruise)
- Inspect O2 sensor wiring for damage or high resistance
- Check for exhaust leaks near sensor location
- Compare sensor response time to specification
- Inspect catalytic converter condition
Repair notes
Replace the upstream O2 sensor Bank 1 if response time exceeds specification.
Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1