Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is having trouble controlling the fuel mixture for one part of the engine. It's like when you can't get the right mix of chocolate and milk for your hot cocoa.
The P1189 code is triggered when the engine control module (ECM) detects a problem with the fuel control for the oxygen sensor located on Bank 2, Sensor 1.
P1189 indicates that the ECM has detected an issue with the fuel control for the upstream oxygen sensor on Bank 2. This sensor is responsible for monitoring the oxygen levels in the exhaust gases before they enter the catalytic converter. If the sensor readings are out of the expected range, it can affect the air-fuel mixture, leading to inefficient combustion.
• Check Engine Light illuminated
• Poor fuel economy
• Rough idle
• Engine hesitation or stalling
• Failed emissions test
• Faulty oxygen sensor
• Wiring issues or poor electrical connections
• Exhaust leaks near the sensor
• Fuel injector problems
• Vacuum leaks
ECM: Engine Control Module
Oxygen Sensor: A device that measures the oxygen level in the exhaust gases
Bank 2: The side of the engine opposite Bank 1, typically the side without cylinder 1
• Use an OBD-II scanner to confirm the code.
• Inspect the oxygen sensor and its wiring for damage.
• Check for exhaust leaks near the sensor.
• Test the sensor's voltage and resistance.
• Inspect fuel injectors and vacuum lines.
• Replace the faulty oxygen sensor.
• Repair or replace damaged wiring or connectors.
• Fix any exhaust leaks.
• Clean or replace fuel injectors.
• Repair vacuum leaks.
• OBD-II scanner
• Multimeter
• Wrench set
• Vacuum gauge
• Fuel injector cleaner
$150 - $400
Moderate
• Chevrolet Silverado
• GMC Sierra
• Cadillac Escalade
• Regular maintenance and inspections
• Use quality fuel and additives
• Promptly address exhaust and vacuum leaks
Sensor Issue
• Get the issue diagnosed and repaired promptly to avoid further damage.
• Regularly check and maintain your vehicle's sensors and wiring.
Check your vehicle's warranty or extended warranty for coverage on emissions-related components.
P1189 has been a common issue in vehicles with aging oxygen sensors or those experiencing exhaust system problems.
Moderate – Addressing this code promptly can prevent further engine performance issues.
Driving with a faulty oxygen sensor can lead to increased emissions and may be illegal in some areas.
• Engine at operating temperature
• Vehicle at idle
The oxygen sensor for Bank 2 Sensor 1 is typically located on the exhaust manifold or exhaust pipe before the catalytic converter on the side of the engine with cylinder 2.
Q: Can I drive with a P1189 code?
A: While you can drive with this code, it's best to address it soon to avoid potential engine damage and increased emissions.
Q: How can I prevent P1189 from occurring?
A: Regular maintenance, including checking sensors and repairing exhaust leaks promptly, can help prevent this code.
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Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
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Fitment Required · Vehicle-fitment part
Relevant when the code or supporting diagnostics point toward upstream or downstream oxygen-sensor faults.
This code family often involves upstream or downstream oxygen-sensor diagnosis.
Verify exact sensor position and vehicle fitment before buying.
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Fitment Required · Vehicle-fitment part
Relevant when catalyst-efficiency or emissions faults persist after proper diagnosis.
Catalyst-efficiency faults sometimes point toward converter problems after proper testing.
Catalytic converters are highly vehicle-specific and should not be purchased by code alone.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.