Abstract: A method for improving the accuracy or precision of a metered fluid includes: estimating a fluidic property of the fluid being metered; and adjusting one or more control parameters based on the estimated property to improve the accuracy or precision of a metered fluid. Preferably, the estimating the property of the fluid being metered includes: monitoring a physical event during the metering operation to collect sensed data; extracting features from the sensed data; and using the features to estimate fluid properties. In another preferred embodiment, the estimated fluidic property is viscosity and the sensed data is a pressure profile during a fluid aspiration. In another preferred embodiment, the method includes a diagnostic analyzer which includes a metering probe having a hard probe or a probe having a disposable tip and wherein the fluid is a body fluid sample.