In gasoline, there are often too many overlapping peaks for resolution of all compounds. More selectivity is needed but use of selective detectors may not work. The 7890A GCs Deans switch allows simplified, and fast 2-dimensional GC analysis. Co-eluting peaks are cut from one column to another of different phase. Compounds that might co-elute with analyte on the first column are separated from analyte on the second column. The oxygenates analyzer includes a split/splitless inlet, pneumatics control module, two columns (pre-column and analytical), two FIDs, and factory checkout. This configuration will meet the ISO EN 13132 method. An autosampler and Agilent ChemStation are strongly recommended.