Assess each of the following statements concerning a brake booster on a vehicle with a diesel engine: ) The diesel engine operates with a surplus of air (no throttle plate to create vacuum). Therefore the master cylinder operates at a positive pressure. The brake booster is connected to the intake manifold. On a diesel engine, the brake booster is connected to a vacuum pump.

Let's assess each statement concerning a brake booster on a vehicle with a diesel engine:<br /><br />1. **The diesel engine operates with a surplus of air (no throttle plate to create vacuum). Therefore, the master cylinder operates at a positive pressure.**<br /> - This statement is **incorrect**. Diesel engines do not use a throttle plate to create a vacuum, but this does not mean the master cylinder operates at a positive pressure. Instead, diesel engines typically use a vacuum pump to provide the necessary vacuum for the brake booster. The master cylinder still operates under vacuum pressure, not positive pressure.<br /><br />2. **The brake booster is connected to the intake manifold.**<br /> - This statement is **incorrect**. In vehicles with diesel engines, the brake booster is not connected to the intake manifold. Instead, it is connected to a vacuum pump, which is a separate component specifically designed to provide the vacuum needed for the brake booster.<br /><br />3. **On a diesel engine, the brake booster is connected to a vacuum pump.**<br /> - This statement is **correct**. Diesel engines often use a vacuum pump to supply the vacuum required for the brake booster. This vacuum pump is separate from the engine's intake manifold and is dedicated to the brake booster system.<br /><br />In summary:<br />- The first statement is incorrect.<br />- The second statement is incorrect.<br />- The third statement is correct.