🔍 Key Concepts

• How the needle valve, nozzle tip, and valve body fit together as a precision assembly • Which parts, if bent, worn, or distorted, could change the alignment between the moving needle and the fixed nozzle seat • The idea that more than one type of damage can produce the same symptom: poor seating or misalignment

💭 Think About

• For each option, ask: would this damage change the straight-line path of the needle or the shape/position of the seat it must seal against? • Think about which components actually guide and support the needle’s movement inside the nozzle body. • Consider whether misalignment can be caused by just one kind of defect, or whether several different defects could all lead to the same misalignment problem.

✅ Before You Answer

• Identify which parts directly contact or guide the needle valve inside the injector. • For each listed defect, decide if it would cause the needle to no longer seat squarely on the nozzle tip. • Before choosing, ask: could more than one of these defects realistically produce the same misalignment symptom?