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Home >> Cadillac >> 1989 >> Seville Base >> Repair and Diagnosis >> Engine Performance >> System >> DFI ECM Tests W/Codes >> Diagnostic Charts >> ECM Code EO30 - Idle Speed Control Circuit Problem >> Notes On Intermittents
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Notes On Intermittents

Display ECM parameter ED01, manipulate TPS wiring and connectors, and see if TPS valve jumps or skips. Enter ECM input EI72, observe throttle switch status light, and check for binding throttle linkage or weak throttle return spring.

Verify that minimum air rate RPM, ISC and TPS are set to specifications. A Code EO30 may be stored along with a Code EO19, SHORTED FUEL PUMP CIRCUIT. If Code EO30 no longer appears after Code EO19 has been corrected, do not investigate any further. The voltage on fuel pump feedback circuit made ECM improperly test Code EO30.

Review snapshot data parameters stored with this code to verify failure. If failure is verified, check and repair intermittent wiring connection or sensor.

Fig 1: ECM Code E030, Idle Speed Control Circuit Problem Schematic
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Fig 2: Flow Chart, Code E030 - Idle Speed Control Circuit Problem
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