Question

A says an intake manifold vacuum leak may cause a cylinder misfire with the engine idling.

B says an intake manifold vacuum leak may cause a cylinder misfire during hard acceleration...

-A
-B
-Both
-Neither

Answer 1

An intake manifold vacuum leak can cause a cylinder misfire with the engine idling and during hard acceleration.

Step-by-step explanation:

A says an intake manifold vacuum leak may cause a cylinder misfire with the engine idling.

B says an intake manifold vacuum leak may cause a cylinder misfire during hard acceleration.

Both A and B are correct. An intake manifold vacuum leak can cause a cylinder misfire in both scenarios. Let's break it down:

1. Engine idling: When the engine is idling, the throttle is mostly closed, and the air-fuel mixture entering the cylinder is controlled by the intake manifold vacuum. If there is a leak in the intake manifold, unmetered air can enter the cylinder, resulting in a lean air-fuel mixture. This can cause a misfire.
2. Hard acceleration: During hard acceleration, the engine requires more air and fuel to produce power. A vacuum leak in the intake manifold can disrupt this air-fuel mixture, leading to a misfire.

Therefore, both A and B are correct.