Signature 520 CM570 Low power no codes

[Signature620]

If you are going to check fuel pressure manually, do not use the test port at the gear pump. That port is to measure inlet restriction and will damage a pressure gauge. The pressure port is at the base of the IFSM near the front.

If you have a vacuum gauge it would be good to check the inlet restriction. I believe the max is 12inhg but I’d have to look it up to be sure.


I also recommend test driving while someone watches a few parameters on Data Monitor. Pay close attention to ‘user fueling state’ (called engine operating state on some engines). A few times I’ve caught CM570s derating with no faults and ended up seeing this state change to FSS Derate. Replacing the crank position sensor solved the problem. Might as well change the cam sensor at the same time.