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Discussion Starter #1
This started happening about a week ago. I thought it might be the cold weather but now I'm thinking it's something else. This only happens on the first cold start of the day for about 1-2 minutes. After that the noise goes away.


What do you guys think it is?
 

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But Mad North-Northwest
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It's hard to hear what's going on there. Try using a mechanic's stethoscope, see if you can nail it down to a specific accessory component or area of the engine.
 

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Sounds possibly like a noisy bearing to me? Not hearing how it sounds when it goes away makes it a little harder to tell.

Kevin
 

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You can remove the fan belt to rule in/out the belt driven items (alternator, water pump). Don't drive it for long but just a brief start up & listen to see if the sound remains or not.

If you don't have a mechanic's stethoscope a 2' - 3' length of heater hose makes a good substitute. It won't amplify the sounds but it'll help narrow down the location. Aim one end at any suspect areas (be careful of hot/moving engine parts) and put your ear at the other end.
 

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I agree with Kevin, it sounds like a bearing on the way out.

I also agree with ghnl about trying to isolate the cause. I don't have a mechanic's stethoscope, but I DO have a gigantic flathead screwdriver that does a wonderful job of transferring sound from whatever it's touching to my ear. You may be able to glean more info this way, as ghnl suggested.
 

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I changed the a/c idler bearing item 2, page 00-29, far right drawing, workshop manual, in our Milano after it started to make those type of sounds until it had run for a couple of minutes, and warmed up I assume. No such sounds since.

You might check that.
 

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I second Del's suggestion. Definitely sounds like a dry bearing if the sound you are referring to is the metallic one I hear.
 

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Discussion Starter #8
Thanks for all of the tips guys. So this morning I cold started it with the intention of checking for the source of the noise and...it didn't make the noise at all! I'm wondering if it is a temperature sensitive thing because it was a lot warmer this morning than it has been recently. I tried checking what I could. Sounds like there is a slight rattling noise when I put the screwdriver to the ps pump, but I don't know if that is normal or not. checked the ac compressor and it sounded fine. Didn't check the alternator because I don't have a screwdriver long enough to reach it. Ran it again this afternoon and it didn't make the noise again. The temperature is supposed to drop a lot this weekend so hopefully I can replicate the noise tomorrow or Sunday.
 

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Check the a/c idler pulley down in front of the engine. It has just a small bearing. You never know.
 

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Discussion Starter #10
Ok! So Saturday I checked again at work but this time with some more experienced mechanics. Luckily we have a mechanic's stethoscope so we checked everything with that. The ps pump is definitely the noisiest. The idler pulley for the a/c is making a little noise but not nearly as much. Don't think it's a belt issue either. Next up is to pull the belt off and see if the pulley is wobbly or not.
 

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Discussion Starter #11
So I asked my shop foreman (who is not an alfa mechanic) what he thought of the ps pump noise. He said it sounds like the pump itself is about to kick the bucket. And on top of that, my car finally made the screeching again this morning and it's not the ps pump! It sounds like it's coming from the ac idler pulley. So do I have a double whammy here? I recorded the ps pump noise. It's the buzzy clicking that gets louder when the camera is closer to the pump.

 

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The a/c idler is not that bad to change. IIRC, everything is just a little tight, not much adjustment in the a/c belt and idler movement. I seem to remember struggling a little with it.

The ps pump of course will make some noise in any event. It is a pump with moving parts.

You say screeching, at cold start up. sure it isn't a loose belt? The 164s have this problem when the serpentine belt is not tight enough. It will screech on a cold start up.
 

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That pump sound like an ordinary rotary hydraulic pump working to me, you know when those power steering pumps are going to die, they really howl. How does the fluid smell, if it is very burnt try putting some new oil in.

I still say just swap out the idler with a known goo done.
 

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Well, difatta lists that they might have several a/c idler pulleys, at ~$80 each, part no 60534564. That's a lot for that. I think I just removed it and bought a new bearing for it from a local bearing outlet.
 

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Discussion Starter #18
I finally got my car to do the screech again after over a week! Now I'm even more confused. Did the screwdriver to the ear check and it sounds like it's the alternator. The nosie was definitely coming from that area at least as I put the screwdriver to the bracket for the alternator.

I also found that the bearing for the a/c idler pulley is Definitely bad. I can wobble the pulley without even taking the belt off or anything. So good call on that one guys.

Here's the screeching sound again. Sounds exactly the same as the last time. No video as my phone is low on memory so it only recorded audio. After two minutes it just faded out to a normal idling sound. Very strange.

 

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Discussion Starter #19
Ok. So got it figured out. Yesterday, my car puked a little bit of coolant and that helped to source the issue. I have a coolant leak from part of the water pump that is dripping down and wetting the alternator belt. So guess I'll take it in and have it looked at. It's weird though as I had the water pump and thermostat replaced just over a year ago. Thanks again for all the help!
 

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That’s a bummer, water pump triggers a timing belt change.
 
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