Dodge Nitro. Manual - part 669

Fig. 53: Fuel Filter/Water Separator Components 
Courtesy of CHRYSLER LLC 

12. Connect electrical connectors (2), (3) and (4).  

13. WATER-IN-FUEL (WIF) SENSOR REPLACEMENT: The combination fuel drain valve/WIF sensor 

is located on the bottom of the fuel filter housing. 

The WIF sensor is not a separately serviceable item. If diagnostics have led you to replace this sensor, 
then the whole fuel filter assembly needs to be changed. 

SENSOR-WATER IN FUEL 

DESCRIPTION 

WATER-IN-FUEL (WIF) SENSOR - ECM INPUT 

 

2007 Dodge Nitro R/T 

2007 ENGINE Fuel System - Nitro

  

Fig. 54: Water-In-Fuel (WIF) Sensor components 
Courtesy of CHRYSLER LLC 

The combination drain valve/Water-In-Fuel (WIF) sensor (6) is located on the bottom of the fuel filter/water 
separator filter canister. 

OPERATION 

WATER-IN-FUEL (WIF) SENSOR - ECM INPUT 

The sensor sends an input to the Engine Control Module (ECM) when it senses water in the fuel filter/water 
separator. As the water level in the filter/separator increases, the resistance across the WIF sensor decreases. 
This decrease in resistance is sent as a signal to the ECM and compared to a high water standard value. Once 
the value reaches 30 to 40 kilohms, the ECM will activate the water-in-fuel warning lamp through CAN bus 
circuits. This all takes place when the ignition key is initially put in the ON position. The ECM continues to 
monitor the input while the engine is running. 

REMOVAL 

WATER-IN-FUEL (WIF) SENSOR 

The Water-In-Fuel (WIF) sensor is located at the bottom of fuel filter/water separator canister. Refer to 
SEPARATOR-FUEL FILTER/WATER for removal and installation procedures. 

HEATER - FUEL 

REMOVAL 

WATER-IN-FUEL (WIF) SENSOR 

The fuel heater is located in the fuel filter/water separator canister housing. Refer to SEPARATOR-FUEL 

 

2007 Dodge Nitro R/T 

2007 ENGINE Fuel System - Nitro

  

FILTER/WATER for removal and installation procedures.

RELAY - FUEL HEATER 

REMOVAL 

REMOVAL 

Fig. 55: Identifying Fuel Heater Relay & Electrical Connector 
Courtesy of CHRYSLER LLC 

The fuel heater relay (1) is located in the left/rear of the engine compartment. 

1. Disconnect negative battery cable.  

2. Disconnect electrical connector (2) from relay.  

3. Remove relay mounting bolt and remove relay.  

4. Check condition of relay connector pins for corrosion, etc.  

INSTALLATION 

INSTALLATION 

 

2007 Dodge Nitro R/T 

2007 ENGINE Fuel System - Nitro

  

Fig. 56: Identifying Fuel Heater Relay & Electrical Connector 
Courtesy of CHRYSLER LLC 

The fuel heater relay (1) is located in the left/rear of the engine compartment. 

1. Check condition of relay connector pins for corrosion, etc.  

2. Position relay and install mounting bolt.  

3. Connect electrical connector (2) to relay.  

4. Connect negative battery cable to battery.  

SENSOR - FUEL TEMPERATURE 

REMOVAL 

WATER-IN-FUEL (WIF) SENSOR 

The fuel temperature sensor is located in the fuel filter/water separator canister housing. Refer to 
SEPARATOR-FUEL FILTER/WATER for removal and installation procedures. 

RAIL - FUEL 

REMOVAL 

REMOVAL 

CAUTION: Cleanliness cannot be overemphasized when handling or replacing diesel 

fuel system components. This especially includes the fuel injectors, high-
pressure fuel lines and fuel injection pump. Very tight tolerances are used 
with these parts. Dirt contamination could cause rapid part wear and 

 

2007 Dodge Nitro R/T 

2007 ENGINE Fuel System - Nitro