P0177 Citroen Fuel Composition Sensor Circuit Range/Performance

P0177 Citroen Fuel Composition Sensor Circuit Range/Performance

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
Tech description
Replaced Fuel Composition Sensor
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
P0177 Citroen Description

Fuel 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.

Citroen Vehicle:2013 Citroen,2012 Citroen,2011 Citroen,2010 Citroen,2009 Citroen,2008 Citroen,2007 Citroen,2006 Citroen,2005 Citroen,2004 Citroen,2003 Citroen,2002 Citroen,2001 Citroen,2000 Citroen,1999 Citroen,1998 Citroen,1997 Citroen,1996 Citroen,