It goes away after a few minutes on a warm day and about 8 to 10 on a cold day - 280,000 miles

 

does the sound change with engine RPMs? change sound if turning vs going straight? Have you done the timing belt and serpentine (drive) belt in a while? I'd suspect one of the idler pulleys or perhaps your power steering pump or alternator - particularly if the noise happens when you are idling in park...

 

It started at about 255,000,the maintenance has always been spot on, I have kept all maintenance records, the sound does change with the revs, it seems to be coming from rear of the engine as you stand I front of the car, as I said once it warms up the sound goes away, it's more of a whirling low frequency whine, when I last changed the serpentine belt at 280,000 it did not go away( could the mech have forgotten to replace something?) there are no performance or emission problems, I have turned the wheel while idling I'll have to wait until the morning to try that, so wait until my next update please, that will be on 2/10/15 about 10am PST west coast USA

 

The growl was from the turbo. I used to let it warm up till 2 "ticks" on temp gauge and then drive - it never worsened. Also let it idle and cool down for 2 mins before shut down and you will be fine.

I drove 25K miles with the growl and it never worsened.

Or you can get a mechanic's stethoscope for cheap from HF and check. Place the receiving end on the heat plate/heat sink over the turbo and try to rev the engine. That's how I found out mine.

Your symptoms are not from the steering rack or from the idlers. The idlers on the serpentine belt will start to "hiss" sort of before they start to growl. Timing belt tension can be inspected - just take the cover off.

 

Should I replace the unit or keep going, will it fail?

 

I run synthetic oil from day one and never let get too dark, changed it at 7000 each time

 

I changed oil every 5000 miles. And as I mentioned let it warm up and cool down every time - never had to replace the turbo. The guy who I sold it to also follows the same and its still running great.

Replace only when you get a CEL and blue plumes of smoke with loss of power. Just keep a note of how long it takes for the sound to go away. I think you should be fine for a while

Also. if it makes you feel any better - I did a trip from Columbus, OH to Caribou, ME to Key West, FL and then back to C'bus at about 294K miles.

 

Thanks