Aqueous compositions for cleaning gas turbine compressor blades

A method of cleaning a gas turbine compressor and the blades thereof during power generation without significant loss of power, which comprises contacting the surfaces to be cleaned with a cleaning composition comprising a mixture of (a) a glycol alkyl ether compound, (b) an alkoxylated surfactant with an alkyl chain length of from about 3 to 18 carbons and (c) a metal corrosion inhibitor component, wherein the mixture has an alkaline metal content less than about 25 ppm, said metal corrosion inhibitor component selected from the group consisting of N-methyloleamidoacetic acid, 1.8-octanedicarboxylic acid, (((2-hydroxyethyl) imino) bis-(methylene)) bis-phosphonic acid N-oxide, ((tetrahydro-2-hydroxy-4H-1,4,2-oxaphosphorin-4-yl)methyl) phosphonic acid N-oxide, and mixtures thereof with triethanolamine.