Engine - Rough Idle/Lack of Power When Passing
90ford04
Article No. 90-4-13
^ PERFORMANCE POOR - 5.8L EFI - WHEN PASSING OR DURING WIDE OPEN THROTTLE - VEHICLES BUILT BEFORE 4/01/89
^ ROUGH IDLE - 5.8L EFI - AFTER 25 SECONDS OF OPERATION - VEHICLES BUILT BEFORE 4/01/89
LIGHT TRUCK: 1988-89 BRONCO, ECONOLINE, F-150, F-250, F-350
CALIBRATION: 8-64E-R10, 8-64H-R10, 8-64R-R10, 8-64S-R10, 8-64W-R10, 8-64Z-R10, 9-64E-R11, 9-64H-R11, 9-64R-R11, 9-64S-R11
WARNING: THIS MODIFICATION IS AUTHORIZED ONLY FOR THE LISTED ENGINE. PERFORMING THIS MODIFICATION ON OTHER ENGINE CALIBRATIONS IS UNAUTHORIZED AND COULD CREATE LIABILITY UNDER APPLICABLE FEDERAL OR LOCAL LAWS.
ISSUE: A lack of power when passing or during wide open throttle may occur when towing a trailer at high ambient temperatures (+95~F, +35~C) and at elevated engine coolant temperatures (+215~F, +102~C). Spark retardation at engine temperatures above 215~F/ 102~C could cause unsatisfactory power. Also, an unusually rough idle may occur after about 25 seconds of idling. The engine idle becomes extremely rough for about 10 seconds, then returns to a typically smooth idle. This is caused by an EEC IV processor strategy error resulting in an extremely lean fuel mixture.
ACTION: Install a new level EEC-IV processor with revised operating strategy. Use the following service procedure.
LACK OF POWER
1. Check to be sure that the engine calibration is listed above.
2. Make sure the customer is aware of Gross Combined Weight (GCW) limitations. Refer to the following Trailer Tow Capability Chart which lists the correct Gross Combined Weights with frontal area restrictions.
3. Perform the inspections listed in Power Diagnostic Routine 209, outlined in the 1989 Engine Emissions Diagnosis Manual, Volume H, Section 2. Perform service procedure(s) as necessary.
4. Perform EEC IV Quick Test. Correct service code(s) as necessary.
5. Replace the EEC IV processor. Refer to the EEC IV Processor Application Chart for correct parts usage.
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 clear plastic decal shield.
ROUGH IDLE
1. Check to be sure that the engine calibration is listed above.
2. Bring the engine to operating temperature and duplicate rough idle condition. The thermactor air should "dump" about 40 seconds into the idle mode, which is part of the catalyst protection logic. Confirm that the "dump" mode exists.
3. Perform the inspections listed in Power Diagnostic Routine 209, outlined in the 1989 Engine Emissions Diagnosis Manual, Volume H, Section 2. Perform service procedure(s) as necessary.
4. Perform EEC IV Quick Test. Correct service code(s) as necessary.
5. Replace the EEC IV processor. Refer to the EEC IV Processor Application Chart for correct parts usage.
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 clear plastic decal shield.
OTHER APPLICABLE ARTICLES: None
WARRANTY STATUS: Eligible Under Basic Warranty Coverage
OPERATION DESCRIPTION TIME
900413A Install EEC IV Processor - 1.5 Hrs.
Econoline
900413A Install EEC IV Processor - 1.2 Hrs.
F Series, Bronco
DEALER CODING
BASIC PART NO. CONDITION CODE
DRIVE 53
OASIS CODES: 620800, 630400, 630401