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Home >> Cadillac >> 1990 >> Seville Base, 4T60/ME9 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> ECM Trouble Code Charts >> ECM Code EO30: Idle Speed Control Circuit Problem >> Note On Intermittents
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Note On Intermittents

Display ECM parameter ED01, manipulate TPS wiring and connectors, and see if TPS jumps or skips. Enter ECM input EI72, observe throttle switch status light and check for binding throttle linkage or weak throttle return spring. Verify minimum air rate RPM, ISC and TPS are set to specifications.

Fig 1: ECM Code EO30 Circuit Diagram
G90I21731
Fig 2: ECM Code EO30 Flow Chart
G90B13707