Escort L4-116 1.9L SOHC HO (1989)
Throttle Position Sensor: All Technical Service Bulletins
Engine - Stalls When Cold
Article No. 90-10-3
STALL- 1.9L CFI - AFTER COLD START DURING A LONG DECEL TO A STOP
FORD:
1987-88 EXP 1987-90 ESCORT
INCOLN-MERCURY: 1987 LYNX
ISSUE:
The engine may stall when it is cold, and the vehicle is driven under a long deceleration to a stop. This occurs because of unique idle speed
adaptive conditions only on some vehicles.
ACTION:
Set the engine throttle position sensor to specification by using the following service procedure.
1. Perform Key On Engine Off and Engine Running Self-Test. Service all codes. Refer to the appropriate Engine/Emissions Diagnosis Manual, Volume
H for service details.
2. Install a breakout box and connect the processor to the breakout box.
3. Warm the engine to operating temperature.
4. With engine OFF...
a. Remove the air cleaner.
Figure 1
b. Connect a jumper wire between the self-test input (STI) and the signal return pin on the self-test connector, Figure 1.
5. Turn the ignition key on, but do not start the engine. The idle speed control (ISC) plunger will retract within 10-15 seconds.
6. Disconnect the vehicle harness from the ISC motor.
7. Turn the ignition key to the OFF position.
8. Remove the jumper wire.
9. Start the engine and run it to normal operating temperature.
10. Check the idle RPM. It should be 600/650 RPM.
