JeffeVerde
Member
- :
- Mazda Protege - 2002
Just replaced the alternator on my daughter's '02 Protege 2.0, fired it up, and it makes this Oh-my-god-I-can-hear-it-from-a-block-away loud, shrill squeal/howl. I shut it off immediately, wondering what went wrong, when my daughter tells me "oh, that's nothing, it's been doing that forever". Pressed for more details, she said it happens every time she starts the car, and goes for about 3-5 minutes, then stops, but that it will sometimes happen while she's driving - mostly when she comes to a stop, and that happens more often when the A/C is on.
I did an extended test drive, doing laps of the same circuit, trying to find some common thread to the problem -- findings --
-it happens at a stops more often than while under way, but it doesn't happen consistently at stops, and it sometimes happens while under way
-it happens more often with the A/C on, but not consistently or continuously
-it happens more often at low RPM, but not consistently, and rev'ing the engine while it's happening has no effect
It's a very high pitched, shrill sound, and sounds like bearings or seizing parts. When it's in full howl, it's too loud to locate more precisely than the pulley side of the engine. Once it's stopped, there's an occasional "chirp", and that seems to be coming from down around the crank/water pump area. Trying to diagnose it, I've--
-run it with the A/C / PS belt removed --- no change - not the A/C or power steering pump
-installed a new alternator (the old one had failed) -- no change -- not the alternator
-replaced the timing belt and idler/tension pulleys (it was due) - no change
-replaced the water pump -- no change
I was sure it was going to be the water pump. But much to my dismay, the car still howled when I fired it up after installing the new water pump.
Short of the crank and cam bearings, I've replaced or disconnected every spinning part. All I can think is maybe a journal bearing is spinning in it's seat intermittently? But I haven't noticed metal in the oil, as I'd expect from a seizing bearing. I'm stumped. Has anyone experienced this, or have any idea what the cause might be?
I did an extended test drive, doing laps of the same circuit, trying to find some common thread to the problem -- findings --
-it happens at a stops more often than while under way, but it doesn't happen consistently at stops, and it sometimes happens while under way
-it happens more often with the A/C on, but not consistently or continuously
-it happens more often at low RPM, but not consistently, and rev'ing the engine while it's happening has no effect
It's a very high pitched, shrill sound, and sounds like bearings or seizing parts. When it's in full howl, it's too loud to locate more precisely than the pulley side of the engine. Once it's stopped, there's an occasional "chirp", and that seems to be coming from down around the crank/water pump area. Trying to diagnose it, I've--
-run it with the A/C / PS belt removed --- no change - not the A/C or power steering pump
-installed a new alternator (the old one had failed) -- no change -- not the alternator
-replaced the timing belt and idler/tension pulleys (it was due) - no change
-replaced the water pump -- no change
I was sure it was going to be the water pump. But much to my dismay, the car still howled when I fired it up after installing the new water pump.
Short of the crank and cam bearings, I've replaced or disconnected every spinning part. All I can think is maybe a journal bearing is spinning in it's seat intermittently? But I haven't noticed metal in the oil, as I'd expect from a seizing bearing. I'm stumped. Has anyone experienced this, or have any idea what the cause might be?