Yilmaz, N., Davis, S., James, J., Ferry, A. et al., "A Novel Method to Evaluate the Combustion Quality of Gasoline Engines: Exhaust Waveform Using AutoEKG Fuel System Analyzer," SAE Int. J. Fuels Lubr. 8(3):560-567, 2015, doi:10.4271/2015-01-9076.
A tool was developed by Illinois Tool Works (ITW) called the “AutoEKG®FSA” (AutoEKG Fuel System Analyzer) which evaluates combustion quality in an engine by measuring the exhaust pulses of the engine. While many factors are known to influence combustion quality and the wave pattern produced by the instrument, the primary factor in this study was the presence of an asphalt-like material in the air intake system. By examining the waveforms measured by the AutoEKGFSA system before and after carbon cleaning, it has been observed that the engines studied not only run better after the removal of carbon in the system, but the improvements may be measured using this system.