Engine - Knock or Cackle
Article No.03-21-39
10/06/03
^ ENGINE - 7.3L DIESEL - ENGINE KNOCK OR
"CACKLE" - 1999-2000 SUPER DUTY F-SERIES AND
2000 EXCURSIONS WITH ENGINE SERIAL
NUMBERS 661894 THROUGH 1311240 - ALL
1998-2000 E-SERIES WITH ENGINE SERIAL
NUMBERS 661974 THROUGH 1311240
^ NOISE - "CACKLE" OR ENGINE KNOCK - 7.3L
DIESEL - 1999-2000 SUPER DUTY F-SERIES AND
2000 EXCURSIONS WITH ENGINE SERIAL
NUMBERS 661894 THROUGH 1311240 - ALL
1998-2000 E-SERIES WITH ENGINE SERIAL
NUMBERS 661974 THROUGH 1311240
FORD:
1998-2000 E SERIES
1999-2000 SUPER DUTY F SERIES
2000 EXCURSION
This article is being published to combine TSB 00-22-1 and 01-14-6 as part of a consolidated 7.3L diagnostic aid booklet.
ISSUE
Some vehicles equipped with a 7.3L Powerstroke diesel engine with engine serial number 661894 through 1311240, may exhibit a noise above the normal sound of the diesel combustion. This noise may sound like a rod knock, but it is intermittent and increases in intensity as the engine warms up to operating temperature. This "cackle" noise may by caused by pressure variation within the fuel rail and in virtually all instances is attributed to cylinder # 8 (driver side rear). The "cackle" noise does not cause damage the engine, or impact the engine's performance or economy.
Engines after serial number 1311240 were built with a long lead injector in cylinder # 8 and correct calibration from the factory. It is possible for engines with the long lead injector, from the factory or installed in service, to exhibit a "lifter noise" (the long lead injector can be identified by the "LL" stamp on top of the solenoid.) This noise is typically most noticeable when the vehicle is parked next to a brick or concrete wall, such as at a fast food drive through. This noise is a normal characteristic of the long lead injector and is not a reason to replace the injector.
ACTION
Refer to the following Service Procedure for diagnostics, injector replacement, and Powertrain Control Module (PCM) reprogramming procedure.
SERVICE PROCEDURE
The "cackle" noise will typically be found early in an engine's life due to low fuel pressure and/or the relationship of injectors and engine firing order, or fuel pressure below specification. If a mature engine develops the "cackle" noise, low fuel pressure is the likely cause. Before making a repair attempt, the following tests should be performed:
1. Verify that the noise occurs with a hot engine, not cold.
2. Verify that the vehicle has been driven long enough to purge the air out of the high-pressure oil system and the fuel system since the last injector/high pressure oil system repair. Air trapped in the system could induce the "cackle" noise.
3. If the fuel pressure is less than 379 kPa (55 psi) in either head, repair it first and re-evaluate the "cackle" concern.
4. Repair any other engine driveability concerns prior to attempting a repair for "cackle". Example: low fuel pressure concerns may be causing low power and "cackle". Repairing the low fuel pressure may correct both concerns. Also, an engine miss may be an indicator of valve train concerns.
5. Verify that there is no air entering the fuel system. Air entering the fuel system will affect injector timing, causing unusual noise/performance.
6. The Injector Performance Analyzer can be used to determine if the "cackle" is coming from cylinder # 8. Cancel that cylinder to determine whether the noise still exists. "Cackle" cannot be identified using the Cylinder Contribution Test.
If the noise is only present when engine is hot, and:
a. no performance concern exists
b. fuel pressure is above the minimum specification of 379 kPa (55 psi)
c. there is no air present in the fuel/oil system
d. a long lead injector is currently not installed
then the engine is a candidate for a special Injector, F81Z-9E527-EARM (engine s/n 661894 - 896811) or XC3Z-9E527-AARM (engine s/n 896812 - end of 7.3L production).
NOTE
IF THE NUMBER EIGHT INJECTOR HAS BEEN REPLACED PREVIOUSLY FOR A CACKLE NOISE CONCERN WITH PART NUMBER NOTED ABOVE, DO NOT REPLACE IT AGAIN. THE LONG LEAD INJECTOR CAN EXHIBIT A TICKING "LIFTER" NOISE AT NORMAL OPERATING TEMPERATURES. THIS IS CONSIDERED A NORMAL CONDITION AND DOES NOT REQUIRE SERVICE.
NOTE
THE ENGINE SERIAL NUMBER CAN BE FOUND ON THE LOWER LEFT SIDE OF THE ENGINE BLOCK REARWARD OF THE OIL FILTER.
NOTE
THE NEW LONG-LEAD INJECTOR FOR "CACKLE" NOISE IS USED ONLY IN CYLINDER # 8. DO NOT USE IN ANY OTHER CYLINDER DUE TO FUTURE CYLINDER CONTRIBUTION TEST DIAGNOSTICS BEING AT RISK. THE INJECTOR IS RECOGNIZABLE BY AN "LL" STAMPED ON THE SOLENOID WHERE THE UVC (INJECTOR HARNESS) CONNECTS.
Replace the # 8 injector by referring to the replacement procedure in the appropriate vehicle Workshop Manual. In addition to replacing the injector, the PCM MUST be reprogrammed to prevent the # 8 injector from flagging a false Cylinder Contribution Test code during future diagnostic tests. After the repair, realize that some small amount of "cackle" may remain.
NOTE
VEHICLES BUILT WITH ENGINE AFTER S/N 1311240 HAVE CORRECT CALIBRATIONS FROM THE FACTORY.
Obtain an Authorized Modifications Decal (FPS 8262 - obtainable through DOES II, 25/pkg) and list the date, dealer number, and summary of modifications 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.
PARTS BLOCK
OTHER APPLICABLE ARTICLES: NONE
SUPERSEDES: 00-22-1, 01-14-6
WARRANTY STATUS: INFORMATION ONLY
Disclaimer