Throttle Position Sensor - No Start Condition
84ford13 Article No. 84-14-17NO START - CFI AND EFI - TPS STICKING
FORD 1983 & 84 ESCORT, EXP, T-BIRD, LTD, CROWN VICTORIA
LINCOLN-MERCURY 1983 & 84 LYNX, COUGAR, MARQUIS, GRAND MARQUIS, MARK VII, CONTINENTAL, LINCOLN
CALIBRATIONS: All with central fuel injection and electronic fuel injection
A "no start" condition can be caused by a sticking or binding throttle position sensor. Use EEC IV Breakout Box to diagnose condition.
NOTE: Sticking or binding of the throttle position sensor in this circumstance has no affect on throttle plate closure within the throttle body.
If the accelerator has been pumped prior to starting the engine, and the TPS sticks in the WOT position, fuel to the injectors will cut off for dechoke functions causing the engine not to start.
The TPS may stick and bind at the WOT position because of over-torqued mounting screws or because of internal conditions such as, rotor spring disengagement, slip-ring terminal shorting to resistive film, and/or moulding epoxy leaking into sensor housing.
Verify TPS operation by the following procedure:
1. Install EEC IV Breakout Box, Special Service Tool #T83L-50 EEC IV, Rotunda 014-00322, or equivalent.
Figure 18:
2. Attach a DVOM, Rotunda #014-00407 or equivalent. Set to the 20 volt scale, and connect the positive (+) lead to pin 47 and the negative (-) lead to pin 46 (Refer to Figure 18).
3. Turn the ignition key to the "RUN" position (do not start engine).
4. While observing the DVOM voltage reading, move the throttle to the wide open position, then back to the idle position.
One of the following conditions will occur:
DVOM voltage will vary from approximately 1 volt to 4 volts and return to original reading. This indicates proper TPS operation. If the "no start" condition still exists, refer to the 1984 Emission Diagnostic Manual, Section 25, Pinpoint Test "A".
DVOM voltage reading - remains at 3.5 volts, or greater. This indicates a malfunctioning TPS. Replace TPS.
IMPORTANT: When replacing TPS on EFI applications, follow replacement instructions outlined in TSB 84-13-6.
5. Torque the two TPS mounting screws to (11 - 16 in.lbs.).
6. Verify TPS operation as stated in Step 4 above.
7. "Breakout Box".
8. Verify satisfactory engine operation.
THROTTLE POSITION SENSOR (TPS) DATE CODING INFORMATION (SENSORS WITH DATE CODES PRIOR TO HC23A SHOULD NOT BE USED FOR SERVICE)
DATE CODE LOCATION:
ON CONNECTOR OF SENSOR BELOW PART NUMBER.
PART NUMBER PART NAME CLASS
E3TZ-9B989-B Throttle Position Sensor A
OTHER APPLICABLE ARTICLES: 83-13-6
WARRANTY STATUS: Reimbursable within the provisions of the Warranty and Policy Manual.
OPERATION: SP9989B84
TIME: 0.5 Hr. DLR. CODING: Basic Part No. 9B989 Code: 41