Bad EGT Reading - sensor is ok

[PhantomPholly]

Today suddenly my #2 EGT started reading 2000+ degrees (about 2048?) with the engine off.  After tracing the wires to ensure no shorts / good continuity and also switching EGT probes and testing for response with a butane lighter on the probe, we determined that it is something inside the EFIS.  Unplugging the connector did not result in this EGT changing (although the other values began to wander).  

Can this be reset, or is this a penalty trip back to the factory?

 

[jakej]

I've found the same problem once - traced it to the pin in dsub connector not being seated home properly, hope this helps.

Jakw J

 

[PhantomPholly]

I thought of that. The pins seem ok, and the reading persists even if I completely remove the connector from the back of the unit (only ONE EGT reads high, the others remain near 60-70 F).

 

[PhantomPholly]

Bump - Hey Dynon, any other thoughts why one EGT would read so high even with the connector disconnected?

 

[dynonsupport]

Without anything connected, the values are free to float, and having one or more EGT that is way out there isn't impossible, or even unexpected. If you short the positive pin to the negative pin of that EGT input, you should see about an ambient temp though. Just for reference, the CHT/EGT inputs are really robust, and basically never fail in the field (although anything is possible). My bet is an open connection somewhere.

 

[PhantomPholly]

Without anything connected, the values are free to float, and having one or more EGT that is way out there isn't impossible, or even unexpected. If you short the positive pin to the negative pin of that EGT input, you should see about an ambient temp though. Just for reference, the CHT/EGT inputs are really robust, and basically never fail in the field (although anything is possible). My bet is an open connection somewhere.

I'll try shorting the pins. Thanks.

 

[RVJack]

I'm having the same problem with a D120 on and IO540 in an RV10. Only one sensor is erratic and it seems to stabalise a small amout with leaning. Any suggestions?

 

[PhantomPholly]

Well, I followed all of Dynon's suggestions and added one of my own. I very lightly crimped the female pin of the offending sensor so that it would have tighter contact on the male pin.

Anyway, the result was that I don't have problems any more when the engine is running.

But, on the ground with the engine off that one EGT will SOMETIMES read sky-high.

At this point I'm just living with it and attributing it to Gremlins.