Is a mild knocking (not injector tick) sound normal on cold idle on the v6 F-Type?
Sound disappears after a few mins:

Cold: Warm:
Piston slap?
Opinions / comparisons appreciated for piece of mind

 

Does not sound like the common SC coupler / torsion isolator rattle to me, something else methinks, but no idea what it might be.

 

If it's any consolation, mine does the same thing. My local dealership replaced the entire SC but it didn't fix it and then said the sound is normal at start-up. It does go away after a few minutes once the engine is warmed up. I'll have them check again in a few months once my car is due for its next service.

 

I had a V6 for three years. When cold it sounded like one kind of '32 Ford tractor. When warm it sounded like another kind of '32 Ford tractor. Same as your videos. The supercharger was also noisy under acceleration, particularly in cold temps.

 

Thanks for the feedback

 

Surprisingly, I seem to have fixed my "knocking while cold" issue. All I did was add a can of BG 44K Platinum to a nearly full tank and the noise nearly disappeared after 50 miles or so. I guess it cleaned whatever was sticking and causing the noise?

 

Most likely one of the injectors.

 

I just put some in both vehicles last month as a preventive maintenance step. (thanks Unhinged).

 

Update in case it helps people- by chance during a service I discovered the garage putting their stock 0w40 oil instead of the JLR certified Castrol 0w20. I played hell and they changed the oil to the recommended type; to my surprise the engine went quiet, could not believe it.
In short the engine design appears very sensitive to oil.

 

ouch. The heavy viscosity must have been messing with the variable cam.

 

Execpt both oils have the same cold viscosity.

 

My understanding that synthetic 0w40 and 0w20 will have the same flow characteristics when cold. So it can't explain cold idle knocking sound.

 

Except both oils have the same thin cold viscosity. So if it runs better after the thin winter weight thickens up, then 10W, 15W or 20W-XX is the right answer since it would eliminate the warm up peroid. That's too be expected as any engine ages.