My Autometer EGT gauge quit working :( Has worked fine for over a year. Just noticed it this morning the needle is buried at the bottom (6 o'clock) position where there aren't any numbers. When I turn the key to "On' the needle jumps up to around 100 degrees ...then once I start the engine it immediately pegs back to the 6 o'clock position and doesn't move.

Does this mean the probe is bad? I removed the 2 probe wires from the back of the gauge and I get an open reading between the 2 wires ...but wasn't sure what it suppose to read?

Coincidentally I had a SC 5 tranny installed yestereday but in looking at the probe/wires nothing was disturbed. Also have the probe wire ran inside that plastic wire loom stuff so I doubt it's pinched anywhere ...I did inspect the wiring at it looks fine. I was expecting the probe to last longer then 1 year!?

IIRC, thermocouples generate voltage when heated. A good one reads 0 ohms (short)

Mine definately reads open across the 2 leads ...not good if short (0 ohms) is the norm. May have to rethink my setup if I have to run a new probe wire into cab. Good excuse for a Trippin overhead mount I guess.

My Autometer EGT gauge quit working :( Has worked fine for over a year. Just noticed it this morning the needle is buried at the bottom (6 o'clock) position where there aren't any numbers. When I turn the key to "On' the needle jumps up to around 100 degrees ...then once I start the engine it immediately pegs back to the 6 o'clock position and doesn't move.

Does this mean the probe is bad? I removed the 2 probe wires from the back of the gauge and I get an open reading between the 2 wires ...but wasn't sure what it suppose to read?

Coincidentally I had a SC 5 tranny installed yestereday but in looking at the probe/wires nothing was disturbed. Also have the probe wire ran inside that plastic wire loom stuff so I doubt it's pinched anywhere ...I did inspect the wiring at it looks fine. I was expecting the probe to last longer then 1 year!?Try relocating the power supply. Just a hunch. Or it might be a bad ground.

Try relocating the power supply. Just a hunch. Or it might be a bad ground.
I don't follow. There isn't any power supply other then the light bulb in the gauge. The probe itself has a yellow and red wire that run directly to the gauge. Not sure what you mean by power supply.

I don't follow. There isn't any power supply other then the light bulb in the gauge. The probe itself has a yellow and red wire that run directly to the gauge. Not sure what you mean by power supply.On the egt gauge at least on my Ultralite there are two screw terminals for the pyro probe +/-
There is also 2 leads one black (ground) one red (switched +) check the connections on these two. Also check the pryo connections while you are at it.
Here is the pdf from Autometer. You might have a different set up, but this is for the Utra Lites http://hp.autometer.com/instruction_download/instructions/551.pdf

Thanks for everyone's help ... I found/fixed the problem. BK Tool, thanks for the PDF link as it reminded me of the probe wire connections down close to the probe (under heat shrink). That's where I found the red wire had come loose from the loop connector that attached to wire on probe side. I just attached a new loop connector and that fixed it! :) I completely forgot about those connection points and was assuming the cable was all one piece from the probe to the gauge. Thanks again.

Another mystery solved by the DP Detectives! :cool: Good work boyz! :grd: JJ :)