High EGT's and low RPM

You wrote

changed the fine filter this afternoon and took the plane up in the pattern.  So far all is good.  If anything bad happens I will let you know.  Otherwise assume that changing the filter solved the problem.

 I took it up again today and it started out fine but soon went back to the same symptoms.  EGT's were all creeping up and the RPM's started to fall.  I landed and checked the course filter and found a little amount of materials

After very short period you notice some materials on the filter. This indicates that something is deteriorating or you have a contaminated fuel.

Sorry for the confusion.  I had not checked the course filter.  When I checked it that was the first time in this effort.  So it had not pulled in additional debris.  That was what had collected for 120 hrs.

UPDATE - Drained all of the fuel and checked for blockages the best I could.  Put it all back together and took it up.  At first it was not improved and I was about to land and pack it up. It was struggling to get 4700 RPM with full throttle.  Both pumps were on and the fuel pressure was in the 46 range which is normal.  

I decided to land and shut it all down for a few minutes.  When I started it back up it was a new engine.  It had power back and acted like normal.  I stayed up and orbited for a while and it worked fine.  

Not sure what to think.  It could be fuel I guess, but it was AVGAS and I put the same fuel back in.  

Will fly again and post what I find.

Paul, I’m no expert, but your symptoms could sound to me like an intermittent electrical failure somewhere although I guess there could be other explanations. Personally, I would not be happy unless I had conclusively tracked it down because I’d be worried about having another episode, however it’s up to you.

If it did happen again, try switching off one ECU lane and see if it goes away. The ECUs are connected to different sensors and if you could isolate the problem to one lane that might help to track this issue down.

...or maybe your disassembly / reassembly dislodged some piece of rubbish that was blocking something and it will never happen again. I have this image in my head of a cat coughing up a fur ball:)

geoffrey klestadt wrote:

Paul, I’m no expert, but your symptoms could sound to me like an intermittent electrical failure somewhere although I guess there could be other explanations. Personally, I would not be happy unless I had conclusively tracked it down because I’d be worried about having another episode, however it’s up to you.

If it did happen again, try switching off one ECU lane and see if it goes away. The ECUs are connected to different sensors and if you could isolate the problem to one lane that might help to track this issue down.

...or maybe your disassembly / reassembly dislodged some piece of rubbish that was blocking something and it will never happen again. I have this image in my head of a cat coughing up a fur ball:)

Thanks Geoffrey,

I am really hoping it is not something in the electronics of the ECU's.  I did try turning off Lane A and B in flight when it was not working right.  It had no effect. What does concern me is that when I landed and shut everything down then started back up it worked fine. To your point I was hoping that something dislodged that was stuck.  But at this point I really don't know what is causing it.  I will fly tomorrow morning and check it again.