EGT gauge wigging out?

[black_cloud_stroker00]

I've got a Autometer z-series EGT gauge. Lately it has been wigging out on me. Under normal driving (light throttle) it will rise to 1200 then max out completely. Shortly after that it will return to normal. I pulled the gauge and felt really hot where the light bulb was. I pulled the fuse and that fixed it.

why would the bulb getting so hot, that it screws with the gauge?

 

[JLDickmon]

high resistance in either the bulb, socket, or ground circuit.

 

[bushpilot]

those <conventional> bulbs get really hot...turn the lights off and
see if the gauge STILL gets hot.

assuming everything else is ok it sounds like you could have a bad
ground or connection in general...check all the wiring...including the
wiring to the probe.

fwiw my egt probe wiring is "spliced" together w/ some screws and
nuts...i THINK most are wired in this way...my point being...that you
should make sure you check the FULL length of wire