Manifold pressure gauge on G1000

[Mlasalle]

Ever since I got my modern glass Mooney 2 years ago, I've had erratic problems with my manifold pressure indicator on the MFD. Several avionics guys have got it working again(a different diagnosis every time), but after a while I start getting erroneous readings again.

It reads a pressure lower than actual, erratic, up and down. The problem has always been a connection somewhere. Usually the large wire harness that goes through the firewall. Take em apart, clean em then back together again and it works fine for a few hours.

There is not a lot of Mooney G1000 avionics repair experience in my area.

Obviously, it's a loose connection, but cannot nail it down.

[29-0363]

Ditto for 29-0363. Have you tried applying contact cleaner to the pins on the bayonet connection? It helps but like you say, the erratic readings reappear.

[Mlasalle]

I don't know which one is the bayonet connection, but I'm sure it's been cleaned. BTY, my avionics guy said never spray corrosion X on connections. It works its way into the circuit boards and eats them up. A garmin no-no. Was told by Premier that hardwiring a separate wire to the MFD, outside the harness, should fix the problem. That means pulling out the panel. I haven't found a technician with the balls to tackle that yet. I'm not sure if I have em,

[Nathan Peterson]

Mlasalle,

 

If you get a chance look at my photo's that I posted and read... I hope this will help you out.  Nate

[Mlasalle]

Thanks Nate, I just figured out the photo thing on the main page and saw your pics.  Imma work on them again.  I noticed you are N490PS, I'm three behind you at N493PS.

[Nathan Peterson]

Mlasalle,

 

I saw the same thing N493PS... I sure hope that helps you out. 

 

Nate

[Nathan Peterson]

What did you come up with?  

[Mlasalle]

I haven't got to it yet. Flew this weekend. It's still bouncing around. I'll give a report as soon as I clean n grease the connections

[Nathan Peterson]

[jeff hodgson]

I have the exact same problem. 2007 o3, this weekend, MP drops, jumps and bounces. I was over mountains at the time so it was very exciting when it first dropped... Soon realized it was just the gauge, but still. What to do now?

[Nathan Peterson]

Mlasalle,

 

What did you come up with?

 

Nate

[neil]

I have the same issue.. Has anyone come up with a solution?

[Bob5151F]

I have had fluctuations on the high and low side.  I even got 32.5" on the takeoff roll, followed by off on high scale (>35). Not bad for a normally aspirated engine. The problem is intermittent and seems to settle down after 10-15 minutes of flying.