Engine - Idle Rough/Stall After Cold Start

90ford47 IDLE - ROUGH - 1.6L EFI - AFTER COLD START - VEHICLES BUILT AFTER 11/02/87

^ STALL - 1.6L EFI - AFTER COLD START - VEHICLES BUILT AFTER 11/02/87
Article No. 90-26-4
LINCOLN-MERCURY: 1988-89 TRACER
ISSUE: A rough idle or stall may occur after a cold engine start. These conditions generally happen in warmer weather and when higher than 87 octane rated fuel is used. The engine may actually run lean in the brief time before the idle air bypass system starts controlling warm engine idle speed.

ACTION: Confirm that only 87 octane rated fuel is being used. If the engine idle and ignition timing is correct, and there are no self test codes in the MECS system, install a vacuum delay kit. Refer to the following procedure for service details.

Figure 1:

SOLENOID VALVE INSTALLATION

1. Connect the vacuum hose and fuel pipe to the solenoid valve.

2. Install the solenoid valve on the bracket as shown in Figure 1.

3. Disconnect the vacuum hose from the surge tank.

4. Connect the fuel pipe to the surge tank. Clip the pipe to the bracket.

5. Connect the vacuum hose to the to the vacuum hose which was disconnected in Step # 3. Clip the hose to the bracket.

Figure 2:

6. Connect the brown connector (C249), attached with the emission wire harness near the vacuum switch solenoid valves located on the cowl, Figure 2.

7. Modify the VECI decal with a Sharpi pen to indicate the new vacuum routing. Also affix a Vehicle Modification Label to the vehicle indicating TSB 90-26-4 was performed.

Figure 3:

WIRE HARNESS INSTALLATION

1. Install the control unit (timer) to the heater bracket as shown in Figure 3.

Figure 4:

2. Disconnect the front wire harness connector (C102), Figure 4.

Figure 5:

3. Connect the harness supplied in the kit between the two C102 connectors that were disconnected in Step # 2, Figure 5.

4. Connect the white six pin connector of the kit harness to the control unit (timer), Figure 5.

5. Disconnect the ECA center connector.

Figure 6:

6. Connect the brown wire from the kit harness to the brown wire (Pin 2K) from the ECA center connector. Use a butt splice connector and seal with shrink wrap, Figure 6.

7. Reconnect the ECA center connector.

8. Fasten the wire harness with bundling straps.

ADJUSTIDLE

1. Adjust the idle speed to the upper limit of the specification according to the VECI decal.

2. Confirm that there is no vacuum applied to the fuel pressure regulator for 15 seconds after starting the engine (warm or cold).

PART NUMBER PART NAME CLASS

E8GY-9D474-C Vacuum Delay Kit CG

OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: Eligible Under Basic Warranty Coverage, Emissions Warranty Coverage
OPERATION DESCRIPTION TIME
902604A Install Vacuum Delay Kit 0.9 Hr
DEALER CODING
BASIC PART NO. CONDITION CODE
9D474 J4
OASIS CODES: 607000, 607400, 608000, 608400