Hi all, I have an -14A with the YIO 390, and the other day I noticed the manifold pressure fluctuating from 19-26 without pilot input. I was aiming for 23" MAP and 2300 RPM, but could not get the engine to stabilize there as it normally would. The engine at the time was leaned as I always do.
Some other considerations:
- The airplane is normally hangared but was outside the prior night. I pulled the cowling and saw no obvious loose hose clamps or damaged wires / lines.
- Mag 2 is showing a 250 RPM drop while Mag 1 is showing 50
- I have not checked to see if I have SB'd Kavlico sensor, but I will soon
Here's a normal flight profile (from the previous day)
Here's the flight where I first noticed the manifold pressure issue.
And here's a ground run-up test I did the following day showing a similar fluctuating MP.
I am having a hard time finding a mechanic who is available so any guidance is appreciated.
Some other considerations:
- The airplane is normally hangared but was outside the prior night. I pulled the cowling and saw no obvious loose hose clamps or damaged wires / lines.
- Mag 2 is showing a 250 RPM drop while Mag 1 is showing 50
- I have not checked to see if I have SB'd Kavlico sensor, but I will soon
Here's a normal flight profile (from the previous day)
Here's the flight where I first noticed the manifold pressure issue.
And here's a ground run-up test I did the following day showing a similar fluctuating MP.
I am having a hard time finding a mechanic who is available so any guidance is appreciated.
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