P0177 - Fuel Composition Sensor Circuit Range/Performance
P0177 Possible Causes
- Flexible Fuel (FF) sensor to Vehicle Power (VPWR) circuit harness open or shorted
- FF to VPWR circuit poor electrical connection
- Open in FF sensor signal circuit
- Short to ground in FF sensor signal circuit
- Fuel contamination
How is the P0177 code repair?Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.
What is the cost to diagnose the P0177 code
Labor: 1.0The cost to diagnose the P0177 code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.
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- Engine Light ON (or Service Engine Soon Warning Light)
P0177 MeaningFuel Composition Sensors are used to determine the amount of ethanol alcohol in the gasoline. Normally, a gasoline engine should not have more than 10% ethanol alcohol in the fuel for proper operation. Some vehicles have a Flexible Fuel (FF) system on them that allow them to run on up to 85% ethanol alcohol in the fuel. The fuel composition sensor sends a frequency modulated signal to the engine controller which is proportional to the alcohol content of the fuel. The injector pulse width and the ignition timing are modified for the increased alcohol content. It takes almost twice the amount of alcohol compared to gasoline to produce the same power.
More InformationNeed more information on how to fix the P0177 code?
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Information for specific makes
- P0177 MERCEDES-BENZ Fuel Composition Sensor Circuit Range/Performance