Question

During a cylinder balance test on an engine with fuel injection, one cylinder provides very little rpm drop.

Tech A says the ignition system may be misfiring on that cylinder.
Tech B says the engine may have an intake manifold vacuum leak.

-A only,
-B only,
-A & B,
-Neither ,

Answer 1

Tech A and Tech B both provide plausible explanations for the cylinder with low RPM drop during a cylinder balance test on an engine with fuel injection. Tech A suggests an ignition system misfire, while Tech B proposes an intake manifold vacuum leak.

Step-by-step explanation:

Tech A and Tech B both provide possible explanations for the very little RPM drop in one cylinder during a cylinder balance test on an engine with fuel injection. Tech A suggests that the ignition system may be misfiring on that cylinder, while Tech B proposes that the engine may have an intake manifold vacuum leak. Both explanations are plausible and can cause the observed behavior.

An ignition misfire occurs when the spark plug fails to ignite the air-fuel mixture in the cylinder, leading to incomplete combustion. This can result in reduced power output and a small RPM drop in the affected cylinder. On the other hand, an intake manifold vacuum leak can cause an imbalance in the air-fuel mixture across cylinders, leading to uneven combustion and a similar decrease in RPM.

Therefore, both Tech A and Tech B can be correct in their respective explanations. The correct answer is -A & B.