GPH reads Zero

[JohnWF]

A few flights ago my fuel flow K-factor changed by itself, and read very low. Reset K-factor and all seemed back to normal.
This morning GPH reads zero. I checked K-factor (normal) Then I changed from TEXT to DIAL and back...no difference. Tried changing K-factor...no help.

About 150 flight hours ago this also happened. At that time I removed the fuel flow 'cube' to clean it..no debris  or dirt of any sort found, and impeller turned freely. Upon reassembly, GPH worked fine. Its a lot of work to pull that cube, but I may have to. I really suspect an oddity within my D-180 inasmuch as the K-factor had just self-changed recently.
Hints?

 

[Dynon]

The k-factor weirdness is odd, and we honestly don't have an explanation for that. The skeptical side of us wonders if it actually changed or whether you were seeing an incipient sensor issue, which made you adjust the K-factor, which seemingly-improved the performance. On the other hand, if you knew what the K-factor was, it wasn't that anymore, and you put it back and it fixed it, that might point to an issue with the D180.

As for getting no reading at all - that does sound more like the sensor itself. If all you did last time was take things apart and put them back together, one thing you did was re-do the electrical connections. Failed connections are perhaps the leading cause of a sensor going away entirely, and it's often the easiest thing to try before actually removing and checking the sensor itself.

 

[JohnWF]

The "no GPH" problem was solved. I opened the fuel flow sensor's three connecting wires, applied a clone of DeOxit and reconnected. This morning the GPH indication worked fine, a bit low, but adjusting the K-factor will take care of this.

 

[DBRV10]

And any reason why the stored K factor changed?

Does not make sense. I wonder if some finger factor was involved?

 

[JohnWF]

No, there was no "finger factor' involved...it takes, as I recall, four different key strokes to get to the setting page, then scroll down to fuel flow, then change...it would take a real spastic person to accidentally input that many correct inputs.

Anyway, the fix was temporary... lasted two flights and I am back to no GPH reading again...have ordered a replacement red cube.