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 has detected that the engine is using more fuel than it should after the exhaust gases have passed through the catalytic converter on one side of the engine.
The P1168 code indicates that the fuel trim system, which adjusts the air-fuel mixture, is having to make excessive corrections to maintain the desired mixture after the catalytic converter on bank 1.
The vehicle's engine control module (ECM) monitors the post-catalyst oxygen sensor to ensure that the catalytic converter is working properly. If the ECM detects that it needs to adjust the fuel mixture significantly to maintain optimal performance, it sets the P1168 code. This can indicate a problem with the catalytic converter, oxygen sensors, or other components affecting the air-fuel mixture.
• Check Engine Light is on
• Poor fuel economy
• Rough idling
• Engine hesitation
• Increased emissions
• Faulty oxygen sensor
• Exhaust leaks
• Faulty catalytic converter
• Fuel injector issues
• Vacuum leaks
Catalytic Converter: A device that reduces vehicle emissions by converting exhaust gases into less harmful substances.
Oxygen Sensor: A sensor that measures the oxygen level in the exhaust gases to help the engine control module adjust the air-fuel mixture.
• Use an OBD-II scanner to confirm the code.
• Inspect the oxygen sensors and wiring for damage.
• Check for exhaust leaks before the catalytic converter.
• Inspect the catalytic converter for damage or clogging.
• Test fuel injectors for proper operation.
• Replace faulty oxygen sensor.
• Repair any exhaust leaks.
• Replace the catalytic converter if necessary.
• Clean or replace fuel injectors.
• Repair vacuum leaks.
• OBD-II scanner
• Multimeter
• Wrench set
• Vacuum gauge
• Exhaust leak detector
$150 - $1200
Moderate
• Nissan Altima
• Nissan Maxima
• Infiniti G35
• Regular maintenance of oxygen sensors.
• Timely replacement of air filters.
• Use high-quality fuel.
Engine Performance
• Do not ignore the Check Engine Light.
• Seek professional diagnosis if unsure.
• Monitor fuel economy for changes.
Check with the vehicle manufacturer for specific warranty coverage related to emissions components.
This code has been commonly associated with vehicles that have aging catalytic converters or oxygen sensors.
Moderate – Addressing this issue promptly can prevent further engine damage and improve fuel efficiency.
Driving with a faulty emissions system can increase pollution and may be illegal in some areas.
• Engine at operating temperature
• Vehicle in closed-loop operation
The post-catalyst oxygen sensor is located in the exhaust system, downstream of the catalytic converter on bank 1.
Q: Can I drive with a P1168 code?
A: While you may be able to drive, it's not recommended as it can lead to poor fuel economy and potential engine damage.
Q: How can I prevent a P1168 code?
A: Regular maintenance and using quality fuel can help prevent issues leading to this code.
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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.