Tankerpilot75
Well Known Member
My fuel pressure sensor feeding my GRT EIS never has worked correctly. I discovered the builder incorrectly wired the 301 ohm resistor on the lead that is fed by 4.8v line from the EIS. I checked the wiring using the approach outlined in the EIS trouble shooting guide and based on that guide my sensor is now correctly wired up. Here is my problem.
GRT instructions for their HPS-02 (80 psi) sensor says the aux SF should be set at 91 and aux OFF at 15. Those settings gave me very bad fuel pressure readings (idle = 14, climb/ cruise 54-58 psi, decent -2 psi). I then tried the aux SF and OFF settings for the 150 psi sensor and the readings were even worse. When I bought the airplane the EIS settings for the fuel pressure sensor were SF=19 / OFF = 30. This gave me a good cruise fuel pressure reading of ~ 24 to 26 psi but really high psi readings at idle or when I pulled the power back.
Searching Aircraft Spruce for fuel pressure sensors I discovered they sell a 60 psi sensor and when I looked at the sensor instructions on line I noticed they were Van's instructions. This makes me think my installed sensor is the Van's 60 psi VDO sensor. Using the recommended GRT settings for the 80 and 150 psi sensor and extrapolating from them a reading for a 60 psi sensor I compute a SF = 51 and OFF = 11. I haven't tried these new settings yet because the airport where I'm hangared is a one hour drive.
My question is: does anyone else have a 60 psi sensor for fuel pressure setup with their GRT EIS? If so, what do you use use for aux SF and OFF settings? What psi readings do you normally see? (Assuming you also have a IO-360 with Airflow Performance injection.)
GRT instructions for their HPS-02 (80 psi) sensor says the aux SF should be set at 91 and aux OFF at 15. Those settings gave me very bad fuel pressure readings (idle = 14, climb/ cruise 54-58 psi, decent -2 psi). I then tried the aux SF and OFF settings for the 150 psi sensor and the readings were even worse. When I bought the airplane the EIS settings for the fuel pressure sensor were SF=19 / OFF = 30. This gave me a good cruise fuel pressure reading of ~ 24 to 26 psi but really high psi readings at idle or when I pulled the power back.
Searching Aircraft Spruce for fuel pressure sensors I discovered they sell a 60 psi sensor and when I looked at the sensor instructions on line I noticed they were Van's instructions. This makes me think my installed sensor is the Van's 60 psi VDO sensor. Using the recommended GRT settings for the 80 and 150 psi sensor and extrapolating from them a reading for a 60 psi sensor I compute a SF = 51 and OFF = 11. I haven't tried these new settings yet because the airport where I'm hangared is a one hour drive.
My question is: does anyone else have a 60 psi sensor for fuel pressure setup with their GRT EIS? If so, what do you use use for aux SF and OFF settings? What psi readings do you normally see? (Assuming you also have a IO-360 with Airflow Performance injection.)