Dynon EGT issues

I have been having nothing but problems with my EGTs so far. Is seems every flight a different cylinder goes wonky. It seems to happen more when the engine is hot. I have put new terminals on multiple times, i have replaced 1. The one I replaced worked for a couple flights, now it is all over the place again. I would think interference, but the chts are run in the same bundle and they are solid as a rock.

Is it possible I am burning these things out? I have them about 2in from the port. Im not happy with how my engine is running, but I dont think it is bad enough to cause these kinds of swings. The plane has all of 12 hrs on it at this point. I would like to use the egts to help diagnose a slightly rough engine, but I can't trust 2 out of 4 on any given flight.

Has anyone had a similar issue?

I had many issues until I changed the connectors. Search this ?Dumb question - connecting CHT/EGT probe wires?. Back in dec 2018. Couple of solutions offered.

I had the same issues with both egt and cht readings. I replaced the spade connectors with thermocouples from a post on here and they are all working correctly now. The problem is the spade connectors. Omega engineering is the company that I ordered from

SMPW-CC-K-M Yellow EGT
SMPW-CC-K-F Yellow EGT
SMPW-CC-J-M Black CHT
SMPW-CC-J-F Black CHT

Replaced the original spade connectors with the ones Latech recommends.I can confirm absolutely zero issues since.

Awesome, thanks everyone. I'll swap the connectors

I went ahead and ordered the K-Type connectors. I ordered through Newark. Price was the same, but shipping was half.

I recently did the update with the connectors. The upgraded connectors seem to work better, but time will tell. At the time of the connector replacement I had 2 EGT's that were being flakey. Red X on boot up. Sometimes they would come alive and work fine after startup. Sometimes not. One of the EGT probes mysteriously just lost 100 degrees during a flight and then after that was always -100 degrees from the other probes. I replaced 2 of them right before Oshkosh, and then the one EGT probe that had been fine up to then decided to go to EGT heaven and it died. I just replaced that probe this week while doing my post-Oshkosh oil change. Hopefully, I can again get all 4 EGT probes registering again!
These things fail, and I think in 700 hours I've gone through 7 or 8 of these. Very annoying!

I offer that the standard spade connectors are not the root problem. It is the wires on the probe side of the connectors. In other words, the probe wire is a real pain to get a good crimp on the spade connector. The EMS side connector is not a problem.

My cure - I wrap the probe side wire around a stripped piece of #20 wire, then crimp this twisted pair in the spade connector (use real AMP connectors, not the auto store junk). After crimping trim off the #20 wire that is sticking out of the connector.

Side note - I don?t know for fact but it seems Dynon got a new suppler for these probes and the new ones I?ve gotten seem to fair better. That said, EGT probes don?t last forever.

Carl

My probes all came already terminated. I did notice the new probe has a better connector, but that one has gone wonky as well. I have less than 13hrs on these probes, and 2 to 3 act up on any given flight. Maybe i will put new terminals on one probe while I wait for the new connectors.