EGT & CHT probe failures

[lavallejd]

Has anyone else experienced excessive EGT/CHT probe failures? We have had our HDX system for just under a year (135 hours) and I’ve already had to replace 2 EGT and CHT probes, then this morning one of the new EGT probes is failing again. They are easy enough to replace, but the failure rate seems excessive. I’m wondering if there is something else I should be looking at.

Failure mode is that the reading jumps all over the place and eventually X’s out, generally within the next flight or two.

Good morning everyone. I wanted to comment on these threads for some time but haven’t had the time. I too had a huge reliability issue with the Dynon EGT probes and was replacing at least one every oil change cycle. After replacing all 4 cylinder probes at least 4 times I said enough. Looking at the aircraft spruce cost of Dynon probes verses JPI probes, it kind of made sense… half the price for half the service (kind of like AT&T). My probes always failed open. Tried to open up the probe but could never determine why, I do know it wasn’t the connector or its crimp. I replaced all 4 with JPI probes and have improved my reliability numbers to what I would expect from a JPI product. Even the Dynon rep at Sun N Fun 2024 suggested I use JPI instead. Who’d a thought…