In this work we study the effect of the excitation of surface plasmons in a metallic cylindrical nanorod by a suddenly created electron-hole pair, using a classical model for the emerging electron and a quantum-mechanical model for the plasmon field in the cylinder. The electron and the hole interact independently with the plasmon field, generating electron density oscillations. Two different trajectories for the emerging electron (parallel to the axis and radial) are studied in an aluminum nanorod. The average number of excited plasmons indicates how important is the role of the hole in the excitation process. We found that the results can be very different according to the trajectory of the emerging electron. We also found that the distinction between intrinsic and extrinsic process is sometimes not applicable.