Engine A/T - High Idle/No Start/MIL ON/Late Shift
Article No.93-18-6
09/01/93
^ IDLE - HIGH - WATER ENTERS THE THROTTLE POSITION SENSOR - 4.6L ENGINE
^ NO START/HARD START - WATER ENTERS THE THROTTLE POSITION SENSOR - 4.6L ENGINE
^ LAMP - MALFUNCTION INDICATOR LIGHT (MIL) ON - WATER ENTERS THE THROTTLE POSITION SENSOR
^ TRANSMISSION - 4R70W - EARLY OR LATE SHIFTING - WATER ENTERS THE THROTTLE POSITION SENSOR
LINCOLN-MERCURY:
1993 MARK VIII
ISSUE:
A no start/hard start condition, MIL light on, erratic transmission shifting and/or a high idle condition may be caused by water entering the throttle position sensor, if a water shield was not installed.
ACTION:
If the above symptoms occur and the throttle position sensor does not have a water shield, replace the sensor and install a water shield. A water shield MUST be installed on the throttle position sensor in a Mark VIII to prevent water from entering the sensor. Refer to the following procedure for service details.
REMOVAL
1. Remove the engine appearance cover. Refer to the 1993 Mark VIII Service Manual, Section 03-01, for the removal procedure.
2. Disconnect the intake air temperature sensor and PCV closure hose.
3. Remove the air inlet assembly from the throttle body.
4. Disconnect the throttle and speed control cables from the throttle body.
5. Disconnect the vacuum fitting and remove the throttle body bolts.
6. Disconnect the throttle position sensor electrical connection, then remove the throttle body and discard the gasket.
7. Remove and discard the throttle position sensor gasket.
INSTALLATION
1. Install the new throttle position sensor.
2. Install the throttle position sensor water shield:
a. Slide the bottom end of the throttle position sensor into the shield.
b. Pull the top over the sensor.
3. Install a new throttle body gasket; apply a small amount of liquid adhesive to each corner of the gasket, then lay it into position on the intake manifold.
CAUTION:
BE SURE TO ALIGN THE THROTTLE BODY GASKET PROPERLY. FAILURE TO DO SO MAY RESULT IN AN UNMETERED AIR LEAK (ROUGH RUNNING CONDITION).
4. Connect the throttle position sensor electrical connector.
5. Install the throttle body onto the intake manifold. Tighten bolts to 8-12 N-m (6.0-8.8 lb.ft.).
6. Connect the speed control, throttle cables and install vacuum fitting(s).
7. Install the air inlet assembly; reconnect the intake air temperature sensor and PCV closure hose.
8. Install the engine appearance cover. Refer to the 1993 Mark VIII Service Manual, Section 03-01, for the installation procedure.
Parts Block
OTHER APPLICABLE ARTICLES: NONE
WARRANTY STATUS:
Eligible Under Bumper To Bumper Warranty Coverage, Emissions Warranty Coverage
OPERATION DESCRIPTION TIME
931806A Replace Sensor And Install 0.7 Hr.
Water Shield
DEALER CODING
BASIC PART NO. CONDITION CODE
9B989 08
OASIS CODES:
206000, 501000, 504000, 602300, 603300, 619400