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We report \hbox{XMM-Newton} observations of two examples of an unclassifiedtype of \hbox{X-ray} weak quasars from the \citet{2020ApJ...900..141P} surveyof \hbox{X-ray} weak quasars in the Chandra archive, SDSS J083116.62+321329.6at $z=1.797$ and SDSS J142339.87+042041.1 at $z=1.702$. They do not belong tothe known populations of \hbox{X-ray} weak quasars that show broad absorptionlines, weak ultraviolet (UV) broad emission lines, or red optical/UV continua.Instead, they display typical quasar UV spectra and spectral energydistributions. In the \hbox{XMM-Newton} observations, both quasars show nominallevels of \hbox{X-ray} emission with typical quasar \hbox{X-ray} spectralshapes (\hbox{power-law} photon indices of $1.99^{+0.27}_{-0.23}$ and$1.86^{+0.15}_{-0.14}$), displaying strong \hbox{X-ray} variability compared tothe archival Chandra data (variability factors of $4.0^{+1.6}_{-1.4}$ and$9.0^{+7.4}_{-3.8}$ in terms of the 2 keV flux density). Simultaneous optical(rest-frame UV) spectra indicate no strong variability compared to the archivalspectra. Long-term optical/UV and infrared light curves do not show anysubstantial variability either. We consider that the \hbox{X-ray} weaknessobserved in the Chandra data is due to \hbox{X-ray} obscuration from asmall-scale dust-free absorber, likely related to accretion-disk winds. Such\hbox{X-ray} weak/absorbed states are probably rare in typical quasars, andthus both targets recovered to \hbox{X-ray} nominal-strength states in the\hbox{XMM-Newton} observations.

XMM-Newton Observations of Two Archival X-ray Weak Type 1 Quasars: Obscuration Induced X-ray Weakness and Variability