ABSTRACT High pressure air fireflooding may have some benefits hitherto not observed at lower pressures. Combustion tube tests were conducted at pressures approaching 3,000 psi. Special start-up procedures were used, especially for the wet burns, to make the testing representative and also minimize the transient effects. The tests indicated: Immiscible displacement of oil by carbon dioxide is an important mechanism at these pressures.The heat-scavenging ability of the water injected along with the air is, as expected, still appreciable at these pressures.