engine knock at low temp?

[Conehead_2467]

hey guys. lately i have noticed that, when cold, i get a little bit of knocking out of the motor. I have some automotive knowledge but i am unsure of this. It is the 3.4L 6 and is jsut below 73k miles. the knock goes away once the engine gets more towards operationg tempurature.

does anyone have any ideas as to what the problem may be? or why this is happening? is there any other info you need from me? any and all info and help is greatly apreciated.

[BNaylor]

Is it a knock or tapping sound?

The GM 3100/3400 60 degree V6 engines are subject to piston slap so that could be the noise you are hearing until the engine warms up. We get in our Alero for about 30 seconds and then it disappears.

[Conehead_2467]

if i had to choose between the two i would probably have to go more with a tapping sound.

EDIT: here is a video i foud on youtube that sounds super similar to what mine does. its a slight knocking right at start up

http://www.youtube.com/watch?v=tTwgzh3ZOnM

[jd-autotech]

loud ass injectors there is a bulliten out on that for the 3.1 and 3.4

[BNaylor]

How long does it take for the noise to disappear? Longer than one minute or less. The tapping is more consistent with piston slap and you really can't tell with the Youtube video posted. Plus it is not a GM 3400 60 degree engine.

Just to be sure what brand oil filter are you using and what brand/weight engine oil? Make sure it is not a cheapy one with a poor anti-drain back valve otherwise you could get dry start noise including the lifters.

If it is piston slap really nothing you can do about it short of an engine tear down and replacing the pistons.

[Conehead_2467]

the noise seems to go away i want to say after a minute or two. i never really timed it.

engine oil: castrol gtx 5w-30 and the filter i would have to check as i cant remember it off of the top of my head. i want to say a fram maybe?