Tech Tip: Kia Optima’s MIL Is On With DTC P0123 Set – UnderhoodService

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Technical resources to help diagnose and repair engine-related service issues.
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Tech Tip: Kia Optima’s MIL Is On With DTC P0123 Set

This bulletin provides information relating to an engine hesitation or the illumination of the Malfunction Indicator Lamp (MIL) for P0123 (Throttle Position Sensor/Switch "A" Circuit High Input). Improper throttle position sensor (TPS) values may cause the engine to hesitate under loads or cause the illumination of the MIL. To correct this condition, the TPS has been improved.

Underhood Service Staff Writers
By Underhood Service Staff Writers
Published:

Affected Vehicle Range:

Related Articles

• 2001-’06 Optima (MS) equipped with 2.5L/2.7L (V6) Delta engine (produced between Oct. 17, 2000 and Aug. 31, 2005)
• 2005-’07 Sportage (KM) equipped with 27L (V6) Delta ­engine (produced between Oct. 28, 2004 and May 18, 2007)

Repair Procedure:

1. Turn the ignition key to the Off position. Open the hood and remove the engine cover. Disconnect the VIS (Variable Induction System) connector and the injector connector, if equipped. See Fig. 1.
fig. 1
2. Disconnect the idle speed control actuator (ISCA) connector and remove the two retaining bolts. ­Remove the ISCA and gasket.

3. Disconnect the TPS connector and remove the two mounting screws.

4. Install the new TPS sensor onto the throttle body and torque the two screws (1.5-2.5 Nm/13.2-21.6 in.-lbs.). Reconnect the TPS connector. See Fig. 2.
Fig. 2
5. Install a new ISCA gasket and re-install the ISCA actuator. Torque the ISCA bolts (6-8 Nm/52.8-69.6 in.-lb.) and reconnect the ISCA connector. Reconnect the VIS connector and the injector connector, if equipped.

6. Reinstall the engine cover.

Courtesy of ALLDATA.

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