High EGT's and low RPM

 Low Fuel pressure = Lean Mixture = High EGT + low RPM.

The ECU does not monitor the Fuel pressure and assumes a properly timed "Squirt" will deliver the proper amount of fuel.

What was the Fuel Pressure?

Check the Fuel Filters.

That is where I was leaning as well.  In the past I could get high fuel pressures, but mainly due to water in MOgas hitting the fine paper filter.  In this case if the pressure is up, it is only slightly.  And with both pumps on it runs better.  But it is relatively easy to change out the fine filter so that is the first place to go.

I agree with Bill

IF you start to see a rise in fuel pressure, it is an indication the fuel filters are starting to become blocked. This is why the Fuel pressure sensor must be installed before the fine filter. 

Also, do you have a gascolator installed? This should trap most water before it gets to the fine filter which you can then drain out before each flight. 

Change your fuel filter and report back!

Never has a truer word been spoken!

Fly the airplane and quit worrying about EGT....CHT and fuel pressures are the most important!

Mike Bush

"High EGTs do not indicate that the engine is under excessive stress, but simply that a lot of energy from the fuel is being wasted out the exhaust pipe rather than being extracted in the form of mechanical energy".

" High EGTs do not represent a threat to cylinder longevity the way high CHTs do. Therefore, limiting EGTs in an attempt to be “kind to the engine” is simply misguided."

"Absolute values of EGT (e.g.,1,475 degrees) are simply not meaningful and are best ignored. There is no such thing as a maximum EGT limit or redline, and trying to keep absolute EGTs below some particular value. If you must fixate on those digital engine monitor readouts, fixate on something important, like CHT"

I provided a link to the PDF that explains this perfectly!

Mr. RTX wrote:

Never has a truer word been spoken!

Fly the airplane and quit worrying about EGT....CHT and fuel pressures are the most important!

Mike Bush

"High EGTs do not indicate that the engine is under excessive stress, but simply that a lot of energy from the fuel is being wasted out the exhaust pipe rather than being extracted in the form of mechanical energy".

" High EGTs do not represent a threat to cylinder longevity the way high CHTs do. Therefore, limiting EGTs in an attempt to be “kind to the engine” is simply misguided."

"Absolute values of EGT (e.g.,1,475 degrees) are simply not meaningful and are best ignored. There is no such thing as a maximum EGT limit or redline, and trying to keep absolute EGTs below some particular value. If you must fixate on those digital engine monitor readouts, fixate on something important, like CHT"

I provided a link to the PDF that explains this perfectly!

 

 

Yep, get all that.  I have attended Mike's class and lived by his teachings.  With the Cirrus that was extremely helpful.  I replaced multiple cylinders based on his teaching.  The EGT's were great for LOP operations.

With that said, the Rotax 912 was telling me something was wrong.  The EGT's are there to tell you something has changed in the engine operation.  With the 912iS the only mechanism I have to manage is the throttle. With EGT's rising it could not be my mixture operation.  And if the EGT's are rising the fuel/air mixture is changing.  Air was unlikely, and it was across all cylinders at the same time so spark was unlikely.  That leaves fuel.  With less fuel getting in the cylinders the EGT's will rise until peak.  

Mike's teachings are great, but the Rotax 912iS requires a bit of modification.