Ive researched the forums and cannot seem to figure out what the problem is.
My 07 tls makes a knocking/rattle ish noise only when i start it up in cold weather after it has sat for a while.
The noise lasts around 2-3 minutes and goes away completely once the car warms up.
There are some days when it does not make the noise, even when the weather is cold, but most of the time it does.
Im not sure if it could be a small exhaust leak or something because the noise began a few weeks after I accidentally ran over a porcupine during the summer.

Any ideas of what is causing this problem?

Also, I could upload a video of the noise if somebody could quickly instruct me how to upload videos to a thread.

thanks guys

 

Anyone?

 

timing belt tensioner

 

heat shield rattling?

 

see I've read about timing belt tensioner, but it does not sound like the noise is coming from the timing belt area. heat shield rattle is a good suggestion. i already removed one side of the head shield on the rear pre-cat due to rattling because it broke off, but it is a good possibility the side i left on is rattling. its just very hard to reach. for those of you experiencing the same problem, ill remove the other shield and post the result.

I began to think it was related to oil level, or it taking a few minutes for oil to reach the rockers or top end. I noticed i was slightly low, still in between the lines but towards the lower end. so i added a little mobile 1 before i started the car and there was no noise.
Any insight on this?

 

I have the same problem on my 04 TL 6mt. Before I bought the car it was neglected to hell and I spent almost 7k just getting it back in working order. It turns out that my knocking is from one of the piston rings mixed with some head damage. I'm saving up to get this thing fixed but it won't be cheap.

 

Mine did the same thing i replaced the serp belt tensioner with no dice, then did a timing belt service and noise is gone! So happy haha.

 

Bump.
I have the same issue.

 

I haven't done my timing bet service but from all of the threads I've read, it seems like that is our problem including mine...I'm gonna do this service within a few weeks

 

I came across this a few times. What I found was out of spec rocker gap to lash caps/valves. They do need to be adjusted every so often. Dont mess with them unless you know how, or you can make things worse. And this includes inspection for hammer wear.