Autopilot Won't Hold Altitude

[dresoccer4]

love this plane! but sometimes encounter this issue. here's what i do:

1) level off at 10,000 feet using autopilot to hold altitude
2) enable NAV autopilot mode
3) the plane then turns to follow course
4) however then the plane begins to climb. no matter what i do she climbes. i enable VS mode and set VS to -1000fpm, but still she climbs. this is with 80% torque
5) i'm watching the elevator trim icon but it doesn't seem to move at all
6) i climbed to altitude with FLC mode just fine

any ideas?

[NeoPyro]

Did you set your altitude with the altitude dial on the autopilot panel before takeoff or press the "ALT" button after you leveled off?

Edited April 20, 2019 by NeoPyro

[Gregg Seipp]

2 hours ago, dresoccer4 said:

love this plane! but sometimes encounter this issue. here's what i do:

1) level off at 10,000 feet using autopilot to hold altitude
2) enable NAV autopilot mode
3) the plane then turns to follow course
4) however then the plane begins to climb. no matter what i do she climbes. i enable VS mode and set VS to -1000fpm, but still she climbs. this is with 80% torque
5) i'm watching the elevator trim icon but it doesn't seem to move at all
6) i climbed to altitude with FLC mode just fine

any ideas?

What does the status bar at the top of the PFD say?

[skdill]

On 4/20/2019 at 2:21 PM, dresoccer4 said:

love this plane! but sometimes encounter this issue. here's what i do:

1) level off at 10,000 feet using autopilot to hold altitude
2) enable NAV autopilot mode
3) the plane then turns to follow course
4) however then the plane begins to climb. no matter what i do she climbes. i enable VS mode and set VS to -1000fpm, but still she climbs. this is with 80% torque
5) i'm watching the elevator trim icon but it doesn't seem to move at all
6) i climbed to altitude with FLC mode just fine

any ideas?

Make sure AP/TRIMS switch (overhead panel - right hand side) is switched to ON and not the middle or lower selection (OFF or AP OFF).  Might seem obvious but I have overlooked it a few times.