Un-answered Knock (not oil or vanos related)

Hello there, I have been having an odd issue with my 2004 325. First off I hate when forums are re posted and already discussed and i did my best to make sure this one was not as far as I saw. Every morning when I start up the car it starts normal and after about 30 seconds it begins to tick. It continues to tick until it is cold again and I start it up the next morning. It does not sound anything like a valve tick it is much slower and not as dense of a sound. The weird thing is it also goes away if i am past 1000 rpm. It first happened right after I returned from a road trip through Nevada. I'm just stumped as to what it may be because its intermediate. Any help is appreciated. Thank you. should i use an oil system cleaner?

Additional info: the noise does stop after long road trips until the engine gets cold again. Also the noise was not present right after I changed my valve cover and my oil to 5W 30. Also untill it is fully warmed up, it has a slightly rougher idle.
_a_

Lifters? Also check if any of your belt drive shafts are wobbling. Especially the water pump pulley.

Thats what I thought at first, however wouldnt the lifters never stop making noise and wouldnt they get louder under load and higher rpm? Its not the pulleys im sure of that. I checked all pulleys and the tensioner and the belt when i did my waterpump, Power steering pump, and the Thermostat 500 miles ago. I also replaced my belt then. I was thinking it could be that one of my lifters is partially clogged and at idle its not getting enough oil, but I do not know. Would a engine treatment solution be worth it? I changed my oil 200 miles ago and the sound went away for about 15 seconds after the first start up. I have also done an HVA bleed but no luck

Originally Posted by Enraged Lineman

Thats what I thought at first, however wouldnt the lifters never stop making noise and wouldnt they get louder under load and higher rpm? Its not the pulleys im sure of that. I checked all pulleys and the tensioner and the belt when i did my waterpump, Power steering pump, and the Thermostat 500 miles ago. I also replaced my belt then. I was thinking it could be that one of my lifters is partially clogged and at idle its not getting enough oil, but I do not know. Would a engine treatment solution be worth it? I changed my oil 200 miles ago and the sound went away for about 15 seconds after the first start up. I have also done an HVA bleed but no luck

Hydraulic lifters make a loud ticking sound like this :



Try removing the belt from the engine if you can to make sure its no auxillary part.

If the knock still exists then possible things could be an anything from exhaust lea to rod knock.

check my thread here and listen to the first video later on in it you will hear a duh duh rattling sound in the background if your sounds similar i was told it most likely is the timing chain tensioner.
http://forum.e46fanatics.com/showthread.php?t=959988

@SweTurbo
I already did that right before i put my fan back on after doing the water pump, the noise seems like its internal but almost deeper. I thought initially it might have been an exhaust leak too but is there any way to check ? the sound is quieter with the hood down. As for the rod knock, what would have caused that ? would it be possible without deeming any performance issues? and what would be the fix for that? But I find it hard to beleive it could be any of those because the sound does go away sometimes. The video you put up sounds a fair bit differnent than mine, and i noticed that your ticking speed changes with throttle significantly. Could i only possibly have one bad lifter?

@gselsidi: im not sure it sounds like that but it may be a possibility because after i did my Vanos the problem went away for a couple of minutes and then came back.

In my vid there was one bad lifter

My best bet would be to have a mechanic look at it , it's hard to diagnose over the web and i dont want to make you buy something you dont have to

@SweTurbo Yes i do agree with you however i have made some progress.

Does anyone know anything about CCV units? i think that the clonking may be related to that. I did some tinkering and when i opened up my oil fill hole it is sucking quite heavily. Right when i opened it up my engine sort of choked and then ran at a lower rpm by the sounds of it. Right after opening it up the noise went away completely. Has anyone heard of this happening before?

I have a similar knock. Mine does it at first start up and goes away after reaching 2000-3000 RPMs. As soon as the car is shut-off and restarted it comes back until reaching the 2000-3000 rpm area.

If it's not present when the engine's cold, and starts up after things get warm, it's probably a tired oil pump. Everything you said lines up with not enough flow output from the pump to keep things happy. That, or some mysterious oil leak internal to the engine (seals, plugs and the like).

To be sure, you could try running a heavier weight of oil and see if the problem stops or gets better.