Hey everyone, new to the forums!

Whenever I start my car, mostly on cold starts, my car makes this awful screaching noise for just a second or two. It seems like it's coming from the driver side either under the hood or just under the car but I cannot pinpoint the source. Any suggestions as to what it might be would be greatly appreciated.

Here is a quick video with the sound I am talking about:
As a side note, I have also been having a different set of chirping/squealing noises under the hood so I just yesterday replaced my serpentine belt. It didn't fix this chirping noise, so I am assuming I also need to replace the pulley/tensioner?

Thanks!

 

That sounds like a grinding sound, not a belt squeal to me. Sounds like the starter is not disengaging after you start to motor. Roll the front of the car up on ramps or jack stands, climb underneath and have a buddy start the car. Listen closely to the starter and see if it is the source of your noise. Otherwise try to pinpoint the source of the noise from above & below the engine. Good luck...

 

AC bearing?

 

Well the sound in the first video is not the separate chirping/squealing noise that made me replace the serpentine belt. I will get my roommate to help me start the car tomorrow to pinpoint the sound from the original video.

This is that separate chirping sound that I said comes from under the hood which is also occasionally accompanied with a squealing noise. The squealing noise is what made me think to replace the belt, though I now know otherwise :


the car is a stock manual 04 v6 with the 3.9L engine

 

I also forgot to mention that the noise in this^ video is not constant. Sometimes it's completely quiet, sometimes it chirps for a few minutes and stops, sometimes it chirps for a while, and sometimes it chirps AND squeals. It's very obnoxious.

 

It is hard to tell from the video, but that is definitely a metal on metal squeak. Hopefully it is just a bad bearing somewhere in one of the accessories or pulleys. Pick up a Mechanics Stethoscope from your local auto parts store ($5) and start poking around for the source of the sound. Good luck...

 

The chirping sound sounds like your alternator. My 99 3.8L does the same screaching noise as in your first video. Never thought too much about it.

 

To check if it's the alternator, take the belt off and turn it with your hand. But mine does the same thing too and it isn't the alternator. I still can't figure it out but it only happens if it is below freezing. Like 40 and above, it doesn't happen.

 

Cam synchronizer. That is EXACTLY what mine sounded like before I replaced it. The upper bushing was junk. In fact, I have a video of it just like yours and you could probably swap the audio and not tell an ounce of difference.

 

Yep, exactly what mine was doing. It also got the point where it would squeal every now and then, especially at low RPM. Like I said above, mine was the cam synchronizer, and sounds exactly like yours in the video. Here is a really crappy video I did when I was just trying to figure out where the sound was coming from. Like you, I checked the pulley's, belts, pumps, alternator, etc and couldn't find anything wrong. Local mechanic pointed me towards the cam synchro and that was it.