Good day everyone!

I recently purchased a 2009 Expedition Eddie B with 40k miles. 5.4L V8.

I'm noticing a light clicking/knocking sound that matches the rpm and disappears around ~2000 rpm. The noise is present when the motor is cold or warm, in any gear.

I can only hear the sound from the inside of the car with the doors shut, but It's definitely coming from the other side of the firewall.

I hope I didn't make a mistake with this beautiful automobile.

Thanks for your help!

 

It wouldn't be the injectors, would it? They're pretty noisy.

 

Thanks for the Reply - slenser.

I shouldn't have included the word "knock". It's a very light tick that I only notice when the engine is idle, or moving slowly. Maybe it's just something I'm not used to...

I hasn't seemed to get any louder.

Thanks again.

 

Mine does it too but Ive narrowed it down to the transmission since it doesn't do it in Park. Id say its more of a clicking sound and not a knock. My Navi is a 2010 with 49,000mi

 

79F150400M,
Does it do it when it's moving only or when it's stopped as well?

 

Only when it's moving between 20 and 40mph and in Drive. Seems to be quieter if I put it in 3rd or 2nd gear.

 

Makes me wonder if there's something in your drive train. Maybe check the driveshaft for something wrapped around it or even something with the tires. Start with the simple possibilities before moving onward.

 

Maybe a cracked exhaust manifold or manifold gasket. Had the issue on both sides 2 years apart. Both covered under ext warrantee