Engine - Detonation At Idle or When Hot

Article No.
93-4-7

February 17, 1993

SPARK KNOCK - 2.3L OHC - DETONATION AT IDLE WHEN AMBIENT TEMPERATURES ARE ABOVE 100 DEGREES (F) 38 DEGREES (C) ENGINE COOLANT TEMPERATURES ABOVE 220 DEGREES (F) 104 DEGREES - VEHICLES EQUIPPED WITH AUTOMATIC TRANSMISSIONS



LIGHT TRUCK: 1992 RANGER


CALIBRATION: 2-50S-ROO, 2-50S-R10

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:
Severe detonation at IDLE when ambient temperatures exceed 100 degrees F (38 degrees C) or engine coolant temperatures exceed 220 degrees F (104 degrees C), may be caused by the calibration of the EEC IV processor.

ACTION:
Confirm that the cooling systems are functioning correctly and the customer is using 87 octane fuel. If detonation is still present, follow the Quick Test procedure as outlined in the 1993 Engine/Emissions Diagnosis Service Manual. If fault codes are present, service them as required. If it is necessary to replace the EEC IV processor with a new processor, refer to the appropriate Light Truck Service Manual for details.





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.



PART NUMBER PART NAME CLASS

F2PZ-12A650-AAA Processor EEC IV B

OTHER APPLICABLE ARTICLES: NONE

WARRANTY STATUS:
Eligible Under Bumper To Bumper And Emission Warranty Coverage

OPERATION DESCRIPTION TIME
930407A Run Quick Test, Replace 0.8 Hr.
EEC IV Processor

DEALER CODING
BASIC PART NO. CONDITION CODE
12A650 07

OASIS CODES: 615000