"markjen" wrote:
I can't think of a scenario which would cause normal EGT, but
CHT 150 deg lower than normal. The engine runs normally.

I'm betting on Ron's #1 choice: a bad connection. First place to look
is the splice between the wire coming from the GEM and the lead coming
from the probe. These are often screw/star washer/ring terminal/nut
affairs that can become loose. They're usually in the engine compartment
covered by sleeves.
--
Dan
C172RG at BFM
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