P2033 – Exhaust Gas Temperature Sensor Circuit (Bank 1 Sensor 2)

What is P2033 and How Serious Is It?

P2033 is an OBD-II generic code that stands for "Exhaust Gas Temperature Sensor Circuit High (Bank 1 Sensor 2)". This code indicates that the powertrain control module (PCM) has detected a high voltage condition in the circuit for the exhaust gas temperature (EGT) sensor located in bank 1, sensor 2.

Can you keep driving with a P2033 code? For now, this issue is not extremely serious and you can usually continue driving carefully. However, it's best to diagnose and fix the underlying problem soon to prevent potential catalytic converter damage from overheating. If the check engine light is flashing or you notice reduced engine performance, it's advisable to have the vehicle checked by a mechanic as soon as possible.

Technical Details of P2033

The EGT sensor is a thermistor that measures the temperature of the exhaust gases, converting it into a voltage signal sent to the PCM. It's located in the exhaust manifold or front exhaust pipe, usually near the catalytic converter. The PCM supplies 5V to the sensor and monitors the return voltage. As exhaust temperature rises, the sensor's resistance decreases, increasing the return voltage. If voltage exceeds a specified threshold (around 3.3V) for more than 1 second, the PCM logs a P2033 code.

The EGT sensor's role is to protect the catalytic converter from damage caused by excessively high temperatures. When the PCM detects high EGT voltage, it will richen the fuel mixture and/or retard ignition timing to cool the exhaust and catalytic converter. On diesel engines, the EGT sensor also helps determine diesel particulate filter (DPF) regeneration timing.

Differences between vehicle makes: P2033 is a generic code that applies to all makes and models from 1996 onwards. However, the exact voltage thresholds, wiring, and troubleshooting procedures may vary between manufacturers. Always consult the factory repair information for vehicle-specific details.

Common Causes of P2033

Potential causes of a P2033 code include:

• Faulty EGT sensor (most common cause)
• Damaged or corroded wiring/connectors in the EGT circuit
• Exhaust leak between the EGT sensor and catalytic converter
• Removal of the catalytic converter and/or EGT sensor
• Faulty PCM (rare)

Diagnosing P2033

To properly diagnose a P2033 code:

1. Scan for all codes and document freeze frame data.
2. Visually inspect the wiring and connectors between the EGT sensor and PCM. Repair any obvious faults.
3. Check for exhaust leaks before the catalytic converter. Repair as needed.
4. If no wiring or exhaust issues are found, disconnect the EGT sensor and see if the voltage reading goes to 5V (indicates open circuit). If not, suspect a short to voltage in the harness.
5. Measure the resistance of the EGT sensor at ambient temperature and compare to specifications. Replace the sensor if out of range.
6. If the sensor and wiring check out okay, the issue may be a faulty PCM, but this is rare. Consult a professional before replacing the PCM.

Repairing P2033

Repairs for a P2033 code may involve:

• Replacing the EGT sensor ($80-200 USD / €70-180 EUR for the part)
• Repairing damaged wiring or connectors ($50-100 USD / €45-90 EUR if no harness replacement needed)
• Fixing exhaust leaks ($100-300 USD / €90-270 EUR depending on location and severity)
• Reinstalling the catalytic converter and EGT sensor if they were removed ($500-1500 USD / €450-1350 EUR for parts and labor)

To prevent P2033, avoid removing emissions control devices, repair exhaust leaks promptly, and address any EGT-related codes immediately to avoid catalytic converter damage. Wiring should also be inspected regularly for damage or corrosion.

Related Issues

Other codes that may appear along with P2033 include:

• P0420 – Catalyst System Efficiency Below Threshold (Bank 1)
• P0430 – Catalyst System Efficiency Below Threshold (Bank 2)
• P0137 – O2 Sensor Circuit Low Voltage (Bank 1 Sensor 2)
• P2032 – Exhaust Gas Temperature Sensor Circuit Low (Bank 1 Sensor 2)

In summary, while a P2033 code does not require immediate engine shutdown in most cases, it should be diagnosed and repaired promptly to prevent catalytic converter damage and ensure proper emissions control. The most likely fix is replacing the EGT sensor, but wiring issues and exhaust leaks should also be ruled out.

Frequently Asked Questions about P2033 Code

What does OBD-II code P2033 mean?

P2033 is a generic diagnostic trouble code (DTC) that stands for "Exhaust Gas Temperature Sensor Circuit High (Bank 1 Sensor 2)". It indicates the powertrain control module (PCM) has detected a high voltage condition in the circuit for the exhaust gas temperature (EGT) sensor located in bank 1, sensor 2.

Where is the Bank 1 Sensor 2 EGT sensor located?

Bank 1 refers to the engine bank that contains cylinder #1. Sensor 2 is the downstream EGT sensor, located after the catalytic converter in the exhaust system. Its exact position varies between vehicle makes and models.

What is the function of the exhaust gas temperature sensor?

The EGT sensor measures the temperature of the exhaust gases exiting the engine. It sends this information as a voltage signal to the PCM. The PCM uses this data to adjust air-fuel ratio and ignition timing to protect the catalytic converter from overheating damage. On diesel engines, the EGT sensor also helps monitor DPF (diesel particulate filter) regeneration.

What are the symptoms of a P2033 code?

Symptoms may include:

• Check engine light illuminated
• Reduced engine performance and fuel efficiency
• Rough idle or misfires
• In some cases, no noticeable symptoms

What are the common causes of a P2033 code?

Potential causes include:

• Faulty EGT sensor (most common)
• Damaged wiring or loose/corroded connector in the EGT sensor circuit
• Exhaust leak between the EGT sensor and catalytic converter
• Removal of the catalytic converter and/or EGT sensor
• Faulty PCM (rare)

Can I keep driving with a P2033 code?

It is not recommended to ignore a P2033 code. While it may not cause immediate driving problems, a faulty EGT sensor can lead to catalytic converter damage from undetected overheating. Continuing to drive the vehicle risks more expensive repairs.

How do I diagnose a P2033 code?

Diagnosis steps include:

1. Scan for all codes and document freeze frame data.
2. Visually inspect the EGT sensor wiring and connectors for damage.
3. Check for exhaust leaks before the catalytic converter.
4. Test the EGT sensor circuit for correct voltage and resistance.
5. If no wiring faults are found, remove and test the EGT sensor.

How much does it cost to fix a P2033 code?

Repair costs for a P2033 code range from $80-$200 for an EGT sensor replacement, to $500-$1500 if the catalytic converter is damaged and needs replacement. Wiring repairs are typically under $100 if no harness replacement is needed.

Can a P2033 code clear itself?

In most cases, a P2033 code will not clear on its own, even if the underlying problem is repaired. The code needs to be cleared with a scan tool or by disconnecting the battery for several minutes.

Is a P2033 code serious?

While a P2033 code does not typically cause immediate drivability issues, it should be addressed promptly to avoid potential catalytic converter damage from undetected overheating. Ignoring this code for too long can result in more serious and expensive problems.

What tools do I need to diagnose a P2033 code?

To properly diagnose a P2033 code, you will need:

• An OBD-II scanner to retrieve codes and freeze frame data
• A digital multimeter to test circuit voltage and resistance
• A repair manual or wiring diagram for your specific vehicle
• Basic hand tools for accessing the EGT sensor and wiring

Can a blown fuse cause a P2033 code?

No, a blown fuse alone will not cause a P2033 code. This code sets when the PCM detects an unexpectedly high voltage in the EGT sensor circuit, not a lack of voltage. However, a short circuit that causes a fuse to blow could potentially cause a P2033.

Will disconnecting the battery clear a P2033 code?

Disconnecting the battery will clear all stored DTCs including P2033. However, if the underlying problem is not fixed, the code will likely return after driving the vehicle for some time. Battery disconnection should not be used as a substitute for proper diagnosis and repair.

How long does it take to fix a P2033 code?

The repair time for a P2033 code depends on the root cause. An EGT sensor replacement typically takes 1-2 hours including diagnosis time. Wiring repairs may take 2-3 hours. Catalytic converter replacement, if needed, can take 3-5 hours.

What happens if I don't fix a P2033 code?

Ignoring a P2033 code can result in:

• Reduced fuel efficiency and engine performance
• Eventual catalytic converter failure from undetected overheating
• Emissions test failure
• More serious engine damage if misfires occur

Will a P2033 code cause my car to fail emissions testing?

In most cases, yes. A P2033 code indicates a problem with the emissions control system, so it will likely cause an emissions test failure. The code must be repaired and the readiness monitors reset before retesting.

How often should I replace my exhaust gas temperature sensor?

There is no specified replacement interval for EGT sensors. They are typically replaced only when they fail and cause a DTC. However, as a sensor ages, its response time may slow down, so replacement may be beneficial for very high mileage vehicles.

Can an exhaust leak cause a P2033 code?

Yes, an exhaust leak between the engine and the EGT sensor can allow outside air to enter the exhaust stream, cooling the exhaust gases. This can cause an unexpectedly low temperature reading, triggering a P2033 code.

Will using the wrong type of fuel cause a P2033 code?

Using improper fuel is unlikely to cause a P2033 code directly. However, certain fuel issues like very low octane or contaminated fuel can cause misfires and catalytic converter damage, which may eventually cause EGT sensor issues if not addressed.

Can a P2033 code damage my engine?

A P2033 code itself does not cause engine damage. However, the root problem that triggered the code, such as an exhaust leak or excessively rich fuel mixture, can lead to engine damage over time if not repaired. Misfires and catalytic converter failure are the main concerns.