Pressurized low olefinic (<2 wt %) hydrocarbon samples in the boiling range of gasoline are analyzed rapidly, accurately, and precisely for paraffin, olefin, naphthene, and aromatic (PNA/PONA) content. A commercially available multidimensional PNA analyzer, configured with packed and micropacked gas chromatographic (GC) columns, is modified by the addition of a liquid sampling valve. In a second GC system, a single nonpolar capillary column is used for a total sample PONA analysis of pressurized low naphthenic/high aromatic hydrocarbon samples (reformate). The results obtained by the two GC methods are compared to conventional compound-type analysis by mass spectrometry (MS).