Greetings,

My check engine light came on the other day, and has been locked in since. I had the code checked at the local auto parts store (Checkers) and it came out to be "P0133 O2 Sensor Circuit Slow Response (Bank 1 Sensor 1)".

Pooling the vast and wise experience of this forum, is this message indicative of a faulty sensor that needs a replacement, or could it be something simpler (i.e. just needs a good cleaning)?

As I understand it, there are two sensors on the car... how do I identify which sensor is "Bank 1 Sensor 1"?

Also, how time consuming is it to replace the sensor? I read from other people's experiences that it can be a pain in the *** to fix due to its remote location. Is this something I should be trying to replace with only a hydraulic jack and jack stands, or would it be better suited to let a shop lift it up.

 

Document ID# 554103
2000 Chevrolet/Geo Corvette


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DTC P0133 HO2S Slow Response Bank 1 Sensor 1




Circuit Description
The powertrain control module (PCM) continuously monitors the heated oxygen sensor (HO2S) activity for 100 seconds. During the monitor period, the PCM counts the number of times that the HO2S responds from rich to lean and from lean to rich and adds the amount of time it took to complete all transitions. With this information, the PCM can determine the average time for all transitions. If the average response time is too slow, a DTC sets.

The PCM determines the lean to rich transition when the HO2S voltage changes from less than 300 mV to greater than 600 mV. The PCM determines the rich to lean transition when the HO2S voltage changes from more than 600 mV to less than 300 mV. An HO2S that responds too slowly is most likely defective. Replace the HO2S.

Conditions for Running the DTC
DTCs P0101, P0102, P0103, P0112, P0113, P0117, P0118, P0125, P0200, P0335, P0336, P0351-P0358, P1120, P1220, P1221, P1258 are not set.
The engine coolant temperature is more than 50°C (122°F).
The ignition voltage is more than 9.0 volts.
The fuel system is operating in Closed Loop.
The engine speed between 1,000 RPM and 2,300 RPM.
The engine air flow is between 20 g/s and 50 g/s.
The EVAP canister purge duty cycle is greater than 0 percent.
The engine run time is greater than 120 seconds.
Conditions for Setting the DTC
The lean to rich response (below 300 mV to above 600 mV) average time is greater than 250 milliseconds.
The rich to lean response (above 600 mV to below 300 mV) average time is greater than 250 milliseconds.
The above conditions are met for 60 seconds.
Action Taken When the DTC Sets
The PCM illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails.
The PCM records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the PCM stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the PCM records the operating conditions at the time of the failure. The PCM writes the conditions to the Freeze Frame and updates the Failure Records.
Conditions for Clearing the MIL/DTC
The PCM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
A last test failed, or current DTC, clears when the diagnostic runs and does not fail.
A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
Use a scan tool in order to clear the MIL and the DTC.
Diagnostic Aids

Important
Remove any debris from the PCM\TAC module connector surfaces before servicing the PCM\TAC module. Inspect the PCM\TAC module connector gaskets when diagnosing/replacing the modules. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM\TAC modules.
For any test that requires probing the PCM or a component harness connector, use the Connector Test Adapter Kit J 35616-A . Using this kit prevents damage to the harness/component terminals. Refer to Using Connector Test Adapters in Wiring Systems.

This diagnostic only runs once per ignition cycle.
A malfunction in the HO2S heater circuits causes a DTC to set. Inspect the HO2S heater circuits for intermittent opens/connections. Refer to Testing for Intermittent and Poor Connections in Wiring Systems.
An oxygen supply inside the HO2S is necessary for proper operation. The HO2S wires provides the supply of oxygen. Inspect the HO2S wires and connections for breaks or contamination. Refer to Wiring Repairs in Wiring Systems.
For an intermittent condition, refer to Symptoms .
Test Description
The numbers below refer to the step numbers on the diagnostic table.

This step determines if the fault is present. This test may take 5 minutes for the diagnostic to run.

When DTCs P0133 and P0153 are set at the same time, is a good indication that a fuel contamination concern is present.

An exhaust leak 6-12 inches away from the HO2S can cause a DTC to set.

This step verifies whether a good ground circuit is available.

This step tests the integrity of the signal circuit to the PCM.

This step tests the integrity of the signal circuit to the PCM.

Certain RTV silicone gasket materials give off vapors that can contaminate the HO2S. There is also a possibility of silicone contamination caused by silicone in the fuel. If the sensors appear to be contaminated by silicone and all the silicone sealant is a non silicone base, advise the customer to try a different fuel company. A missing fuel filler restrictor indicates the customer may have used leaded fuel.

Step
Action
Values
Yes
No

1
Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?
--
Go to Step 2
Go to Powertrain On Board Diagnostic (OBD) System Check

2

Important
If any DTCs are set (except P0153), refer to those DTCs before proceeding with this diagnostic table.


Install a scan tool.
Start the engine and idle at the normal operating temperature.
Operate the vehicle within the parameters specified under Conditions for Running the DTC in the supporting text.
Monitor the DTC Information using the scan tool.
Did DTC P0133 fail this ignition?
--
Go to Step 3
Go to Diagnostic Aids

3
Did DTC P0153 also fail this ignition?
--
Go to Step 8
Go to Step 4

4
Test for an exhaust system leak. Refer to Inspection Procedure in Engine Exhaust. After you inspect the exhaust system, return to this diagnostic.
If you find an exhaust leak, repair the exhaust leak as necessary.
Did you isolate an exhaust leak?
--
Go to Step 14
Go to Step 5

5
Visually/physically inspect the following items:

Ensure that the HO2S is securely installed.
Inspect for corrosion on the terminals.
Inspect the terminal tension at the HO2S and at the PCM.
Inspect for damaged wiring.
Did you find and correct the condition?
--
Go to Step 14
Go to Step 6

6
Disconnect the HO2S.
Jumper the HO2S low circuit (PCM side) to a known good ground.
Monitor the HO2S voltage on the Engine 1 Data List using the scan tool.
Does the scan tool indicate a voltage within the specified range?
350-550 mV
Go to Step 7
Go to Step 10

7
Jumper the HO2S high and low (PCM side) signal circuits to a battery ground.
Monitor the HO2S voltage using the scan tool.
Does the scan tool indicate a voltage below the specified value?
200 mV
Go to Step 13
Go to Step 9

8

Important
Determine and correct the cause of the contamination before replacing a sensor. Inspect for the following conditions:

Fuel contamination
Use of improper RTV sealant
Engine oil/coolant consumption

Replace the affected Heated Oxygen sensor. Refer to Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 and/or Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor 1 .

Is the action complete?
--
Go to Step 14
--

9
Remove the jumper wire from the HO2S low circuit.
Measure the voltage from the HO2S low signal circuit to a battery ground using the DMM.
Does the DMM indicate a voltage near the specified value?
5V
Go to Step 12
Go to Step 11

10
Repair the high signal circuit for a short to ground or a short to voltage. Refer to Wiring Repairs in Wiring Systems.

Is the action complete?
--
Go to Step 14
--

11
Repair the open HO2S low circuit or repair the faulty PCM connections. Refer to Wiring Repairs in Wiring Systems.

Is the action complete?
--
Go to Step 14
--

12
Repair the HO2S high signal circuit for an open or repair the faulty PCM connections. Refer to Wiring Repairs in Wiring Systems.

Is the action complete?
--
Go to Step 14
--

13
Replace the HO2S. Refer to Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 .

Is the action complete?
--
Go to Step 14
--

14
Select the Diagnostic Trouble Code (DTC) option and the Clear DTC Information option using the scan tool.
Start the engine and idle at the normal operating temperature.
Select the Diagnostic Trouble Code (DTC) option and the Specific DTC option, then enter the DTC number using the scan tool.
Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text, if applicable.
Does the scan tool indicate that this test ran and passed?
--
Go to Step 15
Go to Step 2

15
Select the Capture Info option and the Review Info option using the scan tool.

Does the scan tool display any DTCs that you have not diagnosed?
--
Go to the applicable DTC table
System OK



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Document ID# 554103
2000 Chevrolet/Geo Corvette

 

Wow. Thanks for pointing that out to me. Where did you find that resource? Is that a digital version of the service manual?

Also, which is Bank 1 and which is Bank 2? Any experience on what the best way to get at each one is?

 

I'm sure the post above has this but.... the same code came up on chiefDave's car last night and the first thing we checked was fuse 15 under the hood(o2 sensor)....sure enough it was blown(he had some work done on his car that involved removing the headers....) and it solved his problems & saved us a lot of time checking that first.

 

Ttt

 

Bank 1 is Driver's side, bank 2 is passenger's. Sensor 1 is the front O2, sensor 2 is the rear one.

Bank 1 Sensor 1 is Driver's side Front O2 Sensor.

Shane

 

I had the blown fuse as well. I did find, though, that the fuse would keep blowing, but the engine light would come on sporadically. Once I changed the back two sensors, everything was gravy. Ran better, too. If the fuse is blowing, it probably needs something more than just replacing, I've found. But definitely check that fuse.