P0177 - OBD II Trouble Code

Our automotive experts have put together the following information about the P0177 diagnostic trouble code. We've provided the common symptoms that occur when this code is set along with the frequent repairs that address the issues related to the P0177 code.

OBD II Fault Code

• OBD II P0177

OBD-II Code Decreased engine performance is defined as a Fuel Composition Sensor Circuit Range/Performance

vehicle's that are capable of running off of varying levels of ethanol (Flex Fuel, E85), will have a Fuel Composition Sensor in the fuel system so that the engine control module (PCM) can determine the fuel composition and adjust the fuel delivery accordingly. When the PCM detects an incorrect signal from the Fuel Composition Sensor, the PCM will set code P0177.

Decreased engine performance Symptoms

• Decreased engine performance
• Engine may not start
• Increased fuel consumption

Common Problems That Trigger the P0177 Code

• Fuel composition sensor failure
• Powertrain Control Module (PCM) failure
• Powertrain Control Module (PCM) software needs to be updated
• Wiring issue