Some 1997-2003 F-150 vehicles equipped with any engine, and 1997-’98 F-250 LD vehicles equipped with the 5.4L engine, may exhibit a ticking or knocking noise coming from the catalytic converters.
The noise may be described as sounding like a diesel engine.
The condition will be present when the vehicle is in gear at idle only, and is more pronounced when the vehicle is stationary, such as sitting in a drive-thru line.
The noise is normal, and is created by engine pulses being amplified through the light-off converters.
Do not replace the converters unless loose internal components are found.
To reduce the noise, install a wrap kit (P/N 4L3Z-5E258-AC) on each of the light-off converters. Refer to the instruction sheet included in the kit.
Courtesy of IDENTIFIX.
For more information visit: www.identifix.com.