Loud Chirp and Buzz from Aux Water Pump
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R350
Loud Chirp and Buzz from Aux Water Pump
Good morning from NC!
2011 R350 (M272 engine) running rough, engine light appears, pulled P052D code. <facepalm> Auto Zone said it was variable valve timing solenoid bank 2 was retarded - I can't believe that's the terminology.
I disconnected power steering reservoir and removed the oil cooler cover (gasket looked good!) and replaced both solenoids. Everything was pretty easy other than making a mess.
After reassembly and topping off fluids, I cranked up the engine and everything runs smoothly but there's a loud chirp coming from one of the pulleys. It sounds like it's coming from the water pump and the aux water pump buzzes loudly when it kicks on.
Any ideas what I could have done that would have caused that? Would there be air in the system somewhere now? This is a real head scratcher for me.
2011 R350 (M272 engine) running rough, engine light appears, pulled P052D code. <facepalm> Auto Zone said it was variable valve timing solenoid bank 2 was retarded - I can't believe that's the terminology.
I disconnected power steering reservoir and removed the oil cooler cover (gasket looked good!) and replaced both solenoids. Everything was pretty easy other than making a mess.
After reassembly and topping off fluids, I cranked up the engine and everything runs smoothly but there's a loud chirp coming from one of the pulleys. It sounds like it's coming from the water pump and the aux water pump buzzes loudly when it kicks on.
Any ideas what I could have done that would have caused that? Would there be air in the system somewhere now? This is a real head scratcher for me.
Last edited by bteague; Jan 8, 2024 at 11:11 AM. Reason: added detail
MBWorld Fanatic!
Joined: Jun 2014
Posts: 1,086
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From: Melbourne, Australia
2010 ML550 VIN WDC1641722A564750, 2010 B180
Check that your serpentine belt is on the right way. It is possible to attach it the wrong way ( even though it fits) and that you have your water pump working in reverse.
