Noise, except for residual side modes, in mode selection and amplification from optical frequency combs by optical injection locking has not been studied in detail, to our knowledge. We report a numerical study of noise behaviors, including both residual side modes and the noise between them. It reveals that comb laser injection can introduce excessive noise, compared to optical injection with a single mode master laser through the interference between residual side modes and resonances within Arnol'd tongues created by periodic forcing in the optical phase, which can be a severe problem for the case of sub-GHz comb mode spacing. The dependences of residual side mode rejection and phase noise variance on comb mode spacing, seeding power, and detuning are discussed to help in low-noise system design and operation.