SL/R230: 2009 SL550 groaning / bearing noise?
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2009 SL550 R230
2009 SL550 groaning / bearing noise?
My '09 SL550 R230 with 30,000 miles has developed a groaning noise reminiscent of a bearing beginning to fail. It is only heard after the engine warms up ~15 minutes or so of driving. It seems to diminish at highway speeds and gets more pronounced a lower speeds. Both frequency and volume change with engine RPM. The sound doesn't change whether the AC is on or off. It also isn't affected by the transmission state. Revving while coasting at speed in neutral or in the driveway in park the noise changes along with the engine RPM. With the hood open facing the engine it sounds like it is coming from the right front (away from the alternator). It doesn't seem to be affected by steering either.
All these symptoms point away from transmission (my biggest fear), alternator, ac compressor, power steering pump.
What is the likely culprit? Is it possible for the oil pump or water pump to be going out at 30k miles? In two weeks it is due for its 'B' service, which I was planning on doing myself.
Thanks in advance!
All these symptoms point away from transmission (my biggest fear), alternator, ac compressor, power steering pump.
What is the likely culprit? Is it possible for the oil pump or water pump to be going out at 30k miles? In two weeks it is due for its 'B' service, which I was planning on doing myself.
Thanks in advance!
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2009 SL550 R230
Brake fluid level is fine. There are no leaks evident so I doubt it could be a fluid level issue. How do you check abc fluid level? Where is the abc pump located?
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2009 SL550 R230
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'20 X5 M50i; '17 Ram 3500; Golf Cart; Bikes; Scooters
As for checking the ABC & PS fluids, there are 2 black reservoirs at the left front of the engine bay. The upper range of ABC dipstick is engine off, lower range is engine running.
As for your noise, I would suspect an idler pulley bearing, as well as any of the belt driven accessories. Remove the belt (s), then wiggle and spin each pulley or device the belt touches. They should have very little play, and make very little noise. Replace any that fail this test.
It is possible to run the engine briefly (30 seconds) with the belts off to see if the noise goes away. You will get a bunch of warning lights, but it will not hurt anything (same as a failed belt when driving). Let us know what the problem is.
As for your noise, I would suspect an idler pulley bearing, as well as any of the belt driven accessories. Remove the belt (s), then wiggle and spin each pulley or device the belt touches. They should have very little play, and make very little noise. Replace any that fail this test.
It is possible to run the engine briefly (30 seconds) with the belts off to see if the noise goes away. You will get a bunch of warning lights, but it will not hurt anything (same as a failed belt when driving). Let us know what the problem is.
Last edited by kbob999; Sep 20, 2015 at 09:00 AM.
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2009 SL550 R230
I found this post about a bad ABC Pulsation Damper which sounds a lot like my problem. Does anyone have experience with this one? Sound likely?
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2009 SL550
Groaning noise.
I found this post about a bad ABC Pulsation Damper which sounds a lot like my problem. Does anyone have experience with this one? Sound likely?
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2009 CLK550 convertible, 2012 ,,E550 Cabrio, 2012 Audi Q5
Had the same symptoms with my 07 SL550 at 44K. I am willing to bet it is the pulsation dampener. My symptoms started after a loud snap/popping sound coming from engine compartment. I replaced the pulsation dampener after reviewing all the posts and the problem was solved. Be aware that it is probably time to replace all the accumulators since their failure is age dependent not mile dependent. My rear accumulator failed 2 weeks after I replaced the pulsation dampener also with a loud snap/popping sound. I then replaced both accumulators. If you are planning on DIY , be aware that the configuration of the ABC system changed in MY 07 and any "how to" posts on earlier years will not help. If I was not technology challenged I would send you the links to my postings regarding the issues I encountered, however the best I can do is to suggest that you look back to my postings regarding these issues.
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2007 E350; 2018 GLE350
Second the motion re pulsation dampener. Been there. Done that.
To rule it in or rule it out, put an auto stethoscope on the dampener while the engine idles. If the dampener is bad, you'll hear it. And if you don't have a stethoscope, a short length of garden hose will work.
Please let us know how you get this sorted.
To rule it in or rule it out, put an auto stethoscope on the dampener while the engine idles. If the dampener is bad, you'll hear it. And if you don't have a stethoscope, a short length of garden hose will work.
Please let us know how you get this sorted.
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2009 SL550 R230
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2014 SL 550 Sport Package
I have a mechanic stethoscope, however, I don’t know what I’m supposed to hear if I have a bad pulsation dampener. Can anyone offer any guidance? I’m trying to decide if it’s worthwhile changing the pulsation dampener only to address a whining noice at 1,500+ RPMs. If it’s the pump itself, the cost of the pulsation dampener is wasted. My pump was replaced and is only 3-4 years old so I question the pulsation dampener failing but I’d rather that than the pump. FYI, I’ve already replaced the idler pulley and tensioner.
