The nu(2) infrared fundamental of the transient molecule formyl chloride, HCOCl, has been recorded at high resolution. Detailed assignments of the rotational structure have been made for both HCO Cl-35 and (HCOCl)-Cl-37. The nu(2) band, whose origin is at 1784.1377 cm(-1) in (HCOCl)-Cl-35, is predominantly A type with a very weak B-type component. Numerous excited state perturbations occur throughout the band, caused mainly by Delta K-a=2 Fermi resonance and Delta K-a=1 Coriolis interactions with the 3(1)5(1) vibrational state. Even though no "extra" lines resulting from the perturbations could be assigned, a complete analysis of the perturbed rotational structure has been possible. Accurate molecular constants for both the "bright" perturbed 2(1) state and the "dark" 3(1)5(1) perturbing state have been obtained, using a Hamiltonian which includes both the Fermi and Coriolis interactions; only two interaction parameters are needed, one for each mechanism. Further perturbations at high K-a are assigned to Coriolis interactions with the 5(2)6(1) level.