Carwashman

[Carwashman]

I own an '06 STX F150 with the V6. It has 27,000 miles and has always "knocked" when starting the vehicle - sounds like a diesel. Plus, with no load on level ground, it will start knocking or pinging between the speed of 40 and 55 - for no obvious reason. Different grades and brands of gas have no effect on the problem - no codes in the computer - but dealer has heard same problem - just can't figure it out. They changed the EGR valve - no effect. Other than that, they just scratch their heads and agree it is a problem.
Any ideas?

 

[blacksnapon]

I own an '06 STX F150 with the V6. It has 27,000 miles and has always "knocked" when starting the vehicle - sounds like a diesel. Plus, with no load on level ground, it will start knocking or pinging between the speed of 40 and 55 - for no obvious reason. Different grades and brands of gas have no effect on the problem - no codes in the computer - but dealer has heard same problem - just can't figure it out. They changed the EGR valve - no effect. Other than that, they just scratch their heads and agree it is a problem.
Any ideas?

TSB
07-16-17 SPARK KNOCK UNDER LIGHT LOAD AND ACCELERATION - 3.8L, 3.9L, AND 4.2L - SPLIT PORT INTAKE MANIFOLD RUNNER CONTROL (IMRC)

Publication Date: August 7, 2007

FORD: 2001-2004 Mustang
1996-2003 Windstar
1997-2003 E-150
1997-2008 F-150
2004-2007 Freestar
MERCURY: 2004-2007 Monterey


ISSUE:
Various vehicles equipped with a 3.8L, 3.9L or 4.2L engine and Split Port IMRC may exhibit spark knock under light load and acceleration.

ACTION:
Follow the Service Procedure steps to correct the condition.

SERVICE PROCEDURE

Inspect for disconnected IMRC actuator rods.

Check both right hand and left hand side IMRC rods are properly attached to the actuator motor and intake manifold runner.
If the IMRC actuator rods are found to be connected properly, do not continue with this TSB. Refer to Powertrain Control/Emission Diagnosis Manual.
If any IMRC actuator rods are disconnected, refer to Workshop Manual (WSM), Section 303-14 for IMRC service.
If any IMRC actuator rod linkages are found disconnected, replace all four (4) linkage rod retainers.