Engine - Engagement/Deceleration Stalls
Article No. 85-9-27STALLS - ENGAGEMENT/DECEL AFTER INITIAL COLD START - 2.3L HSC CFI
FORD 1985 TEMPO LINCOLN-MERCURY 1985 TOPAZ
Engagement or decel stalls after the first initial cold start, may be caused by the basic vacuum system or EEC IV system malfunction. In order to diagnose which system may be causing the stall concern, the following procedure should be performed.
Figure 27:
1. Check and adjust ignition timing - See Figure 27 shown on page 120.
NOTE: Timing symbol values for 1985 ATX vehicles are different than 1984 ATX vehicles. See Figure 27, page 120.
2. Check for engine vacuum leaks.
3. Perform the EEC IV Quick Test (see 1985 Shop Manual, Volume H) and service any codes as required.
NOTE: If service code 22 is found in the continuous test (memory) portion of the key-on, engineoff self-test, it may be an erroneous code generated by the processor. If code 22 is received in memory, follow TSB 85-2-6 and then proceed.
4. Check for EEC wiring/connector concerns by perform "Wiggle Test" on the following sensors using the corresponding pinpoint test.
SENSOR INPUT PINPOINT
EGR Valve Position (EVP) DD90
Engine Coolant Temperature (ECT) DE90
Air Charge Temperature (ACT) DB90
NOTE: While performing the ACT sensor "Wiggle Test", check the routing of the EEC Harness Wiring to the sensor. If harness is routed too taut, the connector could pull loose creating an intermittent or open circuit.
Throttle Position Sensor (TPS) DH90
Manifold Absolute Pressure (MAP) DF90
NOTE: Also, disconnect the MAP sensor connector and inspect the gray moisture seal for proper connector mating.
Power Steering Pressure Switch (PSPS) FF1
If the LED on the STAR tester goes out during any of the wiggle testing, a fault has been detected and should be serviced as necessary.
5. Check MAP sensor voltage using the MAP/BP Sensor Tester while following pinpoint test DF1. If the sensor is out of the voltage specifications (refer to specifications on back of MAP/BP Sensor Tester), then replace the MAP sensor (Part No. E43Z-9F479-B).
6. Check Fuel System Pressure by following the procedures in TSB Article 85-9-13, shown on page 82.
7. If the vehicle has greater than 300 miles on the odometer then reset the throttle stop screw as follows:
^ Remove throttle body from engine and then remove "welch" plug and reinstall throttle body (skip if plug was removed in Step 7).
^ Start and run engine until it reaches normal operating temperatures.
^ Connect the STAR tester to the vehicle harness.
^ Latch the STAR Tester and run the key-on engine-off (KOEO) self-test.
^ While in the "KOEO" self-test, the ISC motor should retract. When the ISC retracts, disconnect it from the vehicle harness.
^ Unlatch the STAR Tester, connect a tachometer and start the engine.
^ Set parking brake.
^ Place transmission in "Drive" for automatics or "Neutral" for manuals.
^ Reset the throttle stop screw rpm to 550.
NOTE: Idle speeds greater than 550 rpm will prohibit correct adaptive idle learning and may result in speed flare/or extended high idle.
8. Reset the processor Keep Alive Memory (KAM) as follows:
^ Disconnect vehicle battery for approximately 5 minutes.
^ Reconnect battery and initiate the Adaptive Idle Speed Control procedure (TSB Article 85-9-17, page 91) to insure that the processor has "learned" the correct idle RPM (600 in Drive for ATX, 750 in Neutral for MTX).
NOTE: If vehicle processor does not appear to learn the specified idle RPM or the RPM fluctuates, then the throttle stop screw has been set too high or the throttle linkage is being mechanically restrained (i.e., accelerator cable, speed control cable, or throttle plate/ shaft binding).
9. Perform the EEC IV Quick Test and service any codes as required.
Authorized Modifications Decal:
Obtain an Authorized Modifications decal and list the date, dealer number and summary of alterations performed. Select a prominent place adjacent to the Vehicle Emission Control Information decal suitable for installing the Authorized Modifications decal. Clean the area, install the decal and cover it with a plastic decal shield.
PART NUMBER PART NAME CLASS
E43Z-9F479-B Map Sensor A
OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: Reimbursable within the provisions of the Warranty and Policy Manual.
OPERATION: SP12650B85
TIME: 1.8 Hr.
SUPPLEMENTAL OPERATIONS TIME
SP12650B2 -Repair electrical fault 0.3
SP12650B3 -Replace MAP sensor 0.3
SP12650B5 - Reset throttle stop screw 0.6
SP12650B6 -Check throttle linkage 0.1
DLR. CODING: Basic Part No. DRIVE - Code: J8