Ok i have posted about this before with no result, but i will try again. I have a my2003 with a custom exhaust and an aem intake. My car has 50 thousand miles just yesterday. My car makes a noise at idle that is very similar to the sound the car makes when it is about to stall. This noise is present only at idle, once throttle is applied it stops. Also though it resembles the sound of stalling the revs do not drop during this noise. It happens with the ac on or off and when the car is warm or cold.


Any ideas ?

 

I guess I'm not familiar with the rattle a car makes when it is about to stall.

But to try to help diagnose:

Is it a high pitch rattle...more of a buzz? If so it may be lose heatshield. Annoying but not harmful.

Does it sounds like a playing card or credit card in the spokes of a bike? If so it may be your timing chain tensioner. This is bad and needs to be fixed immediately. Part is under $200 and is easy to replace. (See another thread in this forum that discusses more).

Does it sound like your hood is loose? If so it may be your serpentine belt auto tensioner. This is also bad and should be replaced soon. Part is under $100 and is a bit more of a pain to do than the timing chain tensioner. (if a mechanic does it, he may also want to replace the belt which costs under $75).

Also...if it sounds like your hood is lose...well, it just might be.

Good luck...and Gig'M (class of '88 here)

 

Boooooo!!!!

Texas Fight!








edit: Yes, I realize that my post adds no value to this thread whatsoever. But that's only because I have no idea what sound/symptom you're describing.

 

LOL 12-7 Whooop!

 

100-82 Whoooooop lol

 

If it drops down below 800 for a second and feels like it's going to stall ONCE in a while then it's normal

 

I have this rattle that he describes also. With mine it is present only at idle and will continue non-stop until you apply a little gas. It is different from the idle dip that occurs with our car and is also different from a fluctuating idle. Is this what you're trying to describe gotrpms.

In my situation I had a bad TCT that I had replaced. This helped the noise but it is deffinitly still present and is louder in the car than outside the car.

 

Yes that is exactly what i am describing, the noise is easily obscured by the normal engine noise when looking under the hood, but inside the car it is very present. I am about to replace the timing chain tensioner as well, so hopefully that helps. Any other ideas?

 

^ If it's louder in the cabin than in the engine bay, it's probably not the TCT.
Additionally, if 'other engine noise' is louder than what you're describing, then it's probably not the TCT.

I'll take "exhaust leak at the cat" for $500, Alex.

 

I might need to check that because i do have a test pipe, not sure how i forgot that in the first post. Also mxt you have a lot of experience with the TCT. My roommate just blew his motor and he had maybe 50 miles on a new TCT. The new motor he is getting has a new tensioner. Is it worth swapping the new TCT that he barely used for mine with 50 thousand on the clock?