PA-32RT Fuel Flow Issue

[Dean Lefebvre]

We are having trouble figuring out why the fuel flow starts to surge at altitudes above 6,000 msl. RPM fluctuates but MP holds steady. Turning on the standby fuel pump does not help. Switching tanks does not help. Fuel pressure does drop during these surges. We get full power on takeoff and climb until we get higher in altitude. Any ideas?

 

[06CSaratoga]

 

[Heftiger]

 

[Dean Lefebvre]

 

[flyguydon]

 

[06CSaratoga]

 

[Lantraxco]

 

[William OBrien]