Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer thinks that one of the sensors is saying there isn't enough fuel mixed with the air in the engine. It's like if you were baking a cake and didn't have enough sugar, so it doesn't taste right.
The code P1151 indicates that the Heated Oxygen Sensor (HO2S) for bank 2 sensor 1 is not switching properly and is detecting a lean condition (not enough fuel).
The P1151 code is triggered when the Powertrain Control Module (PCM) detects that the upstream oxygen sensor on bank 2 is not switching between rich and lean as expected. This is typically due to a lean condition, meaning there is too much air and not enough fuel in the air/fuel mixture.
• Check Engine Light is on
• Poor fuel economy
• Rough idle
• Faulty oxygen sensor
• Vacuum leaks
• Fuel injector issues
PCM: Powertrain Control Module
HO2S: Heated Oxygen Sensor
• Use an OBD-II scanner to confirm the code.
• Inspect the oxygen sensor and its wiring for damage.
• Check for vacuum leaks in the intake system.
• Replace the faulty oxygen sensor.
• Repair any vacuum leaks.
• Clean or replace fuel injectors if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $300
Moderate
• Ford F-150
• Mazda Tribute
• Lincoln Navigator
• Regular maintenance of the fuel system.
• Check and replace air filters regularly.
• Inspect vacuum lines for leaks periodically.
Sensor Issue
• Address the issue promptly to avoid engine damage.
• Consult a professional mechanic if unsure about repairs.
Check vehicle warranty for coverage on emissions-related components.
This code commonly appears in vehicles with aging oxygen sensors or those that have not been regularly maintained.
Moderate – It should be addressed soon to avoid potential engine performance issues.
Ignoring this code may lead to increased emissions, which can affect compliance with local environmental regulations.
• Engine at operating temperature
• Vehicle at idle
The upstream oxygen sensor (bank 2 sensor 1) is located on the exhaust manifold of the engine's bank 2.
Q: Can I drive with a P1151 code?
A: It's possible to drive, but it's not recommended as it can lead to poor performance and increased emissions.
Q: How do I know if the oxygen sensor is bad?
A: Common signs include poor fuel economy, rough idle, and the Check Engine Light being on.
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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.
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.