P0133
P0133-O2 SENSOR 1/1 SLOW RESPONSEP0133 - O2 Sensor 1/1 Slow Response:
Theory of Operation
For an aged O2 sensor, the response rate to the air/fuel change is slower than when it was new. The O2 sensor tends to move less with the same air/fuel changes in a given time frame. Therefore by observing the activity of voltage readings from the upstream O2 sensor, the quality of the O2 sensor can be detected.
WHEN MONITORED
Vehicle is started and driven between 20 and 55 MPH with the Throttle open for a minimum of 120 seconds. Coolant greater than 70°C (158°F). Catalytic Converter Temp greater than 600°C (1112°F) and EVAP Purge is active.
SET CONDITION
O2 Sensor response is too slow for a calibrated amount of time. Two Trip Fault. Three good trips to turn off the MIL.
POSSIBLE CAUSES
- Exhaust leak
- (K41) O2 1/1 signal circuit
- (K902) O2 return upstream circuit
- O2 sensor
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview
Diagnostic Test
1. ACTIVE DTC
NOTE: Check for contaminants that may have damaged the O2 Sensor: contaminated fuel, unapproved silicone, oil and coolant.
Ignition on, engine not running.
NOTE: After the repairs have been made, verify proper O2 Sensor operation. If all the O2 Sensor voltage readings have not returned to normal, follow the diagnostic procedure for the remaining O2 Sensors.
With a scan tool, read DTCs.
Q: Is the DTC active at this time?
YES: Go To 2
NO: Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Component Tests and General Diagnostics
Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
2. EXHAUST LEAK
Start the engine.
Inspect the exhaust for leaks between the engine and the 1/1 O2 Sensor.
Inspect the exhaust for leaks between the engine and the 1/2 O2 Sensor.
Turn the ignition off.
If a leak is heard but unable to be located, it may be necessary to use special tool Miller Tool #8404A Evaporative Emissions Leak Detector (EELD) on the exhaust system to find leaks.
Connect the SMOKE supply tip (black hose) to the exhaust cone adapter (if equipped) and place it into the tail pipe.
Set the smoke/air control switch to SMOKE.
Press the remote smoke/air start button.
While still holding the remote smoke/air start button, use the white light (#8404-CLL) to follow the EVAP system path, and look for the source of the leak indicated by exiting smoke.
If a leak is concealed from view, release the remote smoke/air start button, and use the ultraviolet (UV) black light #8404-UVL and the yellow goggles 8404-20 to look for residual traces of dye that is left behind by the smoke.
The exiting smoke deposits a residual fluid that is either bright green or bright yellow in color when viewed with a UV light.
Be sure to check the exhaust manifold to cylinder head connection for leaks.
Q: Are there any exhaust leaks?
YES: Repair or replace the leaking exhaust parts as necessary. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
NO: Go To 3
3. (K41) O2 1/1 SIGNAL CIRCUIT
Turn the ignition off
Disconnect the 1/1 O2 Sensor harness connector.
Ignition on, engine not running.
Measure the voltage on the (K41) O2 1/1 Signal circuit in the O2 Sensor harness connector.
Q: Is the voltage between 4.5 and 5.0 volts?
YES: Go To 4
NO: Check the (K41) O2 1/1 Signal circuit for a short to ground, open, or short to voltage. If OK, replace and program the Powertrain Control Module. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
4. (K902) O2 RETURN UPSTREAM CIRCUIT
Measure the voltage on the (K902) O2 Return Upstream circuit in the O2 Sensor harness connector.
Q: Is the voltage at 2.5 volts?
YES: Go To 5
NO: Check the (K902) O2 Return Upstream circuit for a short to ground, open, or short to voltage. If OK, replace and program the Powertrain Control Module. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test
5. O2 SENSOR
If there are no possible causes remaining, view repair.
Repair
Replace the O2 Sensor. Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test