Vans MAP gauge failed high?

[SwimmingDragonfly96]

Hey everyone. On my descent today I glanced down at the MAP gauge and it was pegged on its high limit. Plane was running nice and responding normally to throttle inputs. As I kept going, it seemed to return to normal, kind of hiccuping along the way. Anyone know what could cause this? It’s one of the standard 2-1/4” gauges sold by vans. 7A, o360, CS.

 

[blaplante]

so "high limit" something like 29.9"?

If so then the line/hose that attaches it to the engine has broken / cracked / fallen off

 

[gasman]

High limit??...


The installation instructions also contain troubleshooting procedures.

 

[SwimmingDragonfly96]

High limit??...
View attachment 44763

The installation instructions also contain troubleshooting procedures.

Pegged after 35 on the same gauge thanks for the pic.

 

[pauldan181]

A few years back I was flying home and my plane was slower than normal and just didn't feel right. I diverted to a nearby airport to investigate. After a normal runup and walkaround I noticed my Van's MAP gauge was reading 31" with the engine off, should have been 27-28 at my elevation. A new sending unit cured this until I removed all my Van's engine stuff and replaced with GRT.

 

[Southern Pete]

These gauges are quite well known for EMI problems.
Does it move to full scale when you key the radio?

 

[SwimmingDragonfly96]

These gauges are quite well known for EMI problems.
Does it move to full scale when you key the radio?

I was wondering if it was something like this too. It actually goes towards 0 when I key the mic. I checked it when I landed and it read at 31’ish at my normal airport which is where it always reads there.