im getting this knocking sound on cold starts like only if i let the car sit overnight. i think it just started happening after i havent drove my car for about a week, tephra mod is not picking it up no ses flashing and it goes away once i drive and you never hear it again? if i rev the motor i dont really hear it either. car has cams and some other mods. and im pretty sure its not the clutch, engine oil is full. i posted this in the drivetrain section but it wasent getting attention sorry im really looking for suggestions. This car is so random i dont get it sometimes, i dont even beat on it.

http://i878.photobucket.com/albums/a...p/f379047b.mp4

 

Link does not work!

 

Links updated, car only does this after being off for hours once its warmed up it sounds healthy and runs great i just dont get it

 

bumpppppp

 

i had this issue with my k24 in my rsx. a buddy of mine who is hardcore mustang said that its normal and to not run it hard when its cold. let it warm up a good bit before giving it any throttle

 

i let it warm up for at least 5 before moving the car it just started randomly im scared i dont have money to do a motor rebuild. can it be a pulley or something. maybe piston slap?

 

Bumpppp

 

It's usually piston slap. It happens on motors that are on the "loose" side. I've had a few dsm's do it as well as my current Evo does it ever soo slightly now and then. Unless it's really bad, I wouldn't really worry about it. My last stroker motor did it from day 1 and that car saw 35+ psi from an HX 40 on a daily basis. When torn down it looked fresh as could be.

 

Happens when car settles to 14.9 afr but temp is still very low, once i drive around the motor sounds 100%. Would you consider this Normal? it freaked me out because it just started happening

 

So when you start the car from a cold start, how long does it go on for? Mine is only briefly, say 1-2 sec.

If it goes on much longer then that, and slowly fades with rising engine temp, it VERY well could be a rod knock. I've seen high mileage cars knock like hell on cold starts (think ball peen hammer on a piece of steel), and go dead silent after 2-3 mins of running. When you change your oil next, look for ANY colored shiny stuff in it. Ie: make sure it's a nice clean pan, and check it in the sun after you drain it. If anything is there you will see it glint in the light.

 

Oil was changed less then 1000 miles ago, And my knock sensor isent picking it up. It last for a little ill try again tonight

 

its still making the noise but i really dont think it could be anything that bad its not that loud i mean you can hear it and it goes away as soon as you start driving so i dont know. the knock sensors not flashing i give throttle it does not speed up.

http://i878.photobucket.com/albums/a...p/e9ee0476.mp4

 

bumppppppppp

 

Sound may be coming from the cam gears i put my ear up to it and its loud there, and i started the car today and it wasent that bad today after giving it a good drive last night lol

 

Are you sure it's not just lifter tick then? Or a noisy rocker? Both are pretty common. Without hearing it, it's literally just a guessing game bud.