Combustion diagnostics of a spark ignition engine using a spark plug as an ion probe

Sadami Yoshiyama, Eiji Tomita

Research output: Contribution to journalConference article

17 Citations (Scopus)


It is important to develop the technique for measuring the cycle-to-cycle variation of combustion in order to reduce the fuel consumption of the commercial spark ignition engine. In previous study, we had proposed using the spark plug as an ion probe to measure the appearance time of maximum pressure under the lean mixture conditions of the research engine. In this paper the combustion diagnostics for the commercial engine was performed using the spark plug as an ion probe. Under idling conditions the ion current often appeared during the exhaust process. This ion current is dominated by the flame contact area and the flame velocity. In this case there is good correlation between the characteristic value of the ion current and the indicated mean effective pressure (IMEP). Finally using the spark plug as an ion probe can detect the combustion quality under conditions with large cyclic variation.

Original languageEnglish
JournalSAE Technical Papers
Publication statusPublished - Jan 1 2002
EventPowertrain and Fluid Systems Conference and Exhibition - San Diego, CA, United States
Duration: Oct 21 2002Oct 24 2002


ASJC Scopus subject areas

  • Automotive Engineering
  • Safety, Risk, Reliability and Quality
  • Pollution
  • Industrial and Manufacturing Engineering

Cite this