MIL - Turns ON And OFF Intermittently
89ford03
LIGHT - MALFUNCTION INDICATOR (MIL) - INTERMITTENT OPERATION - 2.3L OHC TURBO - VEHICLES BUILT AFTER 11/01/86
Article No. 89-4-4
FORD: 1987-88 THUNDERBIRD
CALIBRATION 7-06E-R11, 7-05E-R10
ISSUE: A "Check Engine" Malfunction Indicator Light (MIL) that turns "on" and "off" may be caused by an intermittent "rich fuel" condition. The "rich fuel" condition may be caused by one or more fuel injectors or the EEC IV processor. This condition is indicated by service code "42" during continuous self test or a "EGO" that is always rich during idle.
ACTION: Perform the service procedure applicable to the vehicle transmission type to determine if one or more of the fuel injectors and/or the EEC IV processor require replacement. Service code "42" will be displayed during the EEC IV Quick Test indicating a period of rich air/fuel ratio operation. Service code "42" will also be stored in continuous Self-Test memory.
VEHICLES WITH AUTOMATIC TRANSMISSIONS
1. Perform an EEC IV Quick Test, service as required.
NOTE: IF ROUTINE DIAGNOSTICS (PINPOINT TESTS) DO NOT CORRECT THE FAULT, PROCEED TO STEP 2.
2. Install a new level EEC IV processor, (E8SZ-12A650-AGA).
3. Check to see if the condition still exists by doing the following:
a. Warm engine to operating temperature by driving the vehicle for several miles.
NOTE: IF THE ENGINE IS WARMED UP IN NEUTRAL, THE "MIL CHECK ENGINE LIGHT" MAY COME ON BECAUSE THE EEC IV PROCESSOR HAS NOT ADAPTED TO THE FUEL CHARGING HARDWARE.
b. Position the gear selector in drive "D". Idle the engine one (1) minute with the air conditioning "ON" and the blower fan at maximum speed.
c. Shift the transmission into neutral or park. Idle engine for one (1) minute in neutral or park with the air conditioning "ON" and the blower fan still set at maximum speed.
d. Shift the transmission into drive and repeat Steps 3b and 3c with all accessories turned "OFF".
NOTE: THE MALFUNCTION INDICATOR LIGHT "CHECK ENGINE" SHOULD STAY "OFF" DURING ALL IDLE ROUTINES. SERVICE CODE "42" SHOULD NOT APPEAR IN CONTINUOUS MEMORY DURING EEC-IV QUICK TEST IF THE CONDITION IS STILL PRESENT, PROCEED TO STEP 4.
4. Flow test the fuel injectors using the Rotunda Injector/Cleaner, 113-00001. Locate the "BROWN BAND" on the flowmeter. Replace fuel injectors that test above the midpoint of the "BROWN BAND" on the flowmeter.
VEHICLES WITH MANUAL TRANSMISSIONS
1. Perform an EEC IV Quick Test, service as required.
2. Flow test the fuel injectors using the Rotunda Injector/Cleaner, 113-00001. Locate the "BROWN BAND" on the flowmeter. Replace fuel injectors that test above the midpoint of the "BROWN BAND" on the flowmeter.
NOTE: THE YELLOW WARRANTY CODE TAG MUST BE MARKED "MIL" IN THE "REASON REPLACEMENT PART REQUIRED" LINE.
AUTHORIZED MODIFICATION DECAL REQUIRED
Obtain an Authorized Modification 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 Modification Decal. Clean the area, install the decal and cover it with a clear plastic decal shield.
PART NUMBER PART NAME CLASS
E7SZ-9F593-A Fuel Injector B
E8S7-12A650-AGA EEC IV Processor B
OTHER APPLICABLE ARTICLES: None
ARTICLE SUPERSEDED: 88-10-5, date 5/11/88.
WARRANTY STATUS: Eligible Under Basic Warranty Coverage And Under Emissions Coverage If EEC IV Processor Or Injectors Are Defective
OPERATION DESCRIPTION TIME
890404A Automatic Transmission 1.5 Hr.
(replace processor)
890404B Automatic Transmissions 3.1 Hrs.
(replace processor and injectors)
890404C Manual Transmission 2.1 Hrs.
(replace injectors)
DEALER CODING:
BASIC PART NO. CONDITION CODE
MIL 09
OASIS CODES: 2300, 2500