northern pointer

I've a 2008 F150 HD with the 5.4 liter engine. It has about 135,000 kms / 84,300 miles on it. For some time I've been hearing a throaty sound from the engine when accelerating. Otherwise the engine is pretty quiet when idling. Is this throaty sound an indication that the phase shifters are starting to go? Those who have had to replace the phase shifters, did you hear this throaty sound to begin with? Thanks.

SCORGE

Cam phaser failure is loud, audible clacking.
Not sure what you mean by throaty?

BadFish523

Cam phaser failure is as Scorge stated, a clacking sound from the front of the engine only at idle RPMs less than 800 to 1200 and much more prevalent when engine is at operating temp not cold. Please explain your sound better.

Martian

And with the cam phasers, since the VCT system isn't even active until the engine is warm, they usually don't make a sound at all until they reach temp.

SCORGE

do you have an aftermarket intake?

Archangel72

possible exhaust manifold leak? warms up expands and goes away?

BadFish523

FPDM!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!! (kidding)

Taildragger

Foam seal around the airfilter.

BIGDAWG78

yeah Throaty doesnt tell much.... whats MODs are done? CAI and exhaust stuff can be throaty...... and is it a bad throaty or good throat? we need more information.

SCORGE

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