An engine is idling rough and has a lack of power. Which test should be performed first?
A) Cranking compression test
B) Running compression test
C) Cylinder leakage test
D) Cylinder power balance test

Question

Quizplus · Accepted Answer

A cylinder power balance test is the best choice as it can help identify which cylinder(s) are not contributing to the engine's power and causing the rough idle. A cranking compression test, running compression test, and cylinder leakage test may also be necessary, but it is best to perform the power balance test first.

An Engine Is Idling Rough and Has a Lack of Power