DE1 DTC P0176: CHECK VPWR VOLTAGE TO FF SENSOR
NOTE:
To determine whether the vehicle being serviced is an ethanol or methanol application, look at the calibration sticker on the door jamb. A prefix of 610 C indicates an ethanol vehicle. A prefix of 610 G indicates a methanol vehicle. Another method is to refer to the fuel filler door; it will read either METHANOL or ETHANOL.
l Disconnect FF sensor.
l Key on.
l Measure VPWR circuit voltage between the VPWR circuit at the FF sensor harness connector and battery negative post.
l Is the voltage greater than 10.5 volts?
Yes
KEY OFF. GO to «DE2».
DE2 CHECK BATTERY GROUND CIRCUIT FOR OPEN IN HARNESS
l Measure resistance between battery ground circuit at the FF sensor harness connector and battery negative post.
l Is resistance less than 10,000 ohms?
Yes
GO to «DE3».
No
REPAIR open circuit.
DE3 CHECK FF SENSOR SIGNAL CIRCUIT FOR OPEN IN HARNESS
l Measure resistance between FF sensor signal circuit at PCM harness connector and FF sensor signal circuit at the FF sensor harness connector.
l Is resistance less than 5 ohms?
Yes
GO to «DE4».
No
REPAIR open circuit.
DE4 CHECK FF SENSOR SIGNAL CIRCUIT FOR SHORT TO POWER
l Disconnect scan tool.
l Disconnect PCM.
l Measure resistance between FF sensor signal and VPWR circuits at PCM harness connector.
l Is resistance greater than 10,000 ohms?
Yes
GO to «DE5».
No
REPAIR short circuit.
DE5 CHECK FF SENSOR SIGNAL CIRCUIT FOR SHORT TO GROUND
l Measure resistance between FF sensor signal and PWR GND circuits at PCM harness connector.
l Is each resistance greater than 10,000 ohms?
Yes
GO to «DE6».
No
REPAIR short circuit.
It goes on and on until they have you replace the FF sensor or drain out contaminated fuel. Straight gas, the FF sensor puts out a 60Hz signal (actually up to 15% ethanol).
So, basically, check the power to the FF sensor, must be over 10.5v and verify it is getting a ground. If you recently got fuel somewhere odd, maybe it IS contaminated.
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