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In this work, we explore the long-term variability properties of the blazarPKS 0219-164 in the radio and the $\gamma$-ray regime, utilizing the OVRO 15GHz and the \fermi/LAT observations from the period 2008--2017. We found that$\gamma$-ray emission is more variable than the radio emission implying that$\gamma$ ray emission possibly originated in more compact regions while theradio emission represented continuum emission from the large scale jets. Also,in $\gamma$-ray the source exhibited spectral variability characterized by the\emph{ softer-when-brighter} trend, a less frequently observed feature in thehigh energy emission by BL Lacs. In radio, using Lomb-Scargle periodogram andweighted wavelet z-transform, we detected a strong signal of quasi-periodicoscillation (QPO) with a periodicity of 270 $\pm$ 26 days with possibleharmonics of 550 $\pm$ 42 and 1150 $\pm$ 157 days periods. At a time when theissue of the detection of QPOs in blazars is still under debate, the observedQPO with high statistical significance ( $\sim$ 97\% -- 99\% globalsignificance over underlying red-noise processes) and persistent over nearly 10oscillations could make one of the strongest cases for the detection of QPOs inblazar light curves. We discuss various blazar models that might lead to the$\gamma$-ray and radio variability, QPO, and the achromatic behavior seen inthe high energy emission from the source.

Radio and $\gamma$-ray variability in the BL Lac PKS 0219 -164: Detection of quasi-periodic oscillations in the radio light curve