I tried to run the cylinder contribution test yesterday but it would not complete. The error message I'm getting is "Test failed for unknown reasons." What engine parameters need to be in a specific range for this test to be performed? I know the engine oil needs to be hot, I figured that one out already. Does coolant temperature or intake air temperature need to be within range for this test? I'm guessing one of these is the culprit but correct me if I'm wrong. BTW, EOT was ~175F and coolant was ~145F when I ran the test. Don't know what the intake air temp was at the time, but ambient temp has been around ~50 here.

 

I believe the coolant needs to be at least 160 degrees