Loud howling near fuel pump
Thread Starter
Senior Member
Joined: Sep 2014
Posts: 320
Likes: 87
From: Tampa
'01 CLK 430 cab, '04 SL500 (230K miles)
Loud howling near fuel pump
I'm getting a very very loud howling from the fuel pump area. I have already changed the fuel pump and filter. I can make the howl disappear by squeezing a certain spot on the fuel hose which comes out of the fuel filter. If I were restricting the fuel flow somehow and that is making the noise go away, why not at other spots that I'm squeezing. I'm sure there is a logical explaination for this, just don't know what it is.
I made a video of it.
I made a video of it.
Senior Member
Joined: Jun 2013
Posts: 287
Likes: 5
From: New Hampshire
Magma Red W208 55 AMG, W203 C230 Kompressor Sedan 6speed M/T, W220 S500
This is interesting. The only thing I can think of is, maybe that section of the hose has collapsed on itself and by you squeezing that section, you are opening it back up. Just a thought. Hope you find a solution to this.
Thread Starter
Senior Member
Joined: Sep 2014
Posts: 320
Likes: 87
From: Tampa
'01 CLK 430 cab, '04 SL500 (230K miles)
Good point, I didn't think I might be actually opening the hose. I Shudda tried rotating the squeeze at that spot. The car has been running fine, even at 140mph a few weeks ago. I'd think there might be some hesitation or stumbling but maybe it is open just enough not to cause a problem. I'll replace the hose in any case.
Senior Member
Joined: Jun 2013
Posts: 287
Likes: 5
From: New Hampshire
Magma Red W208 55 AMG, W203 C230 Kompressor Sedan 6speed M/T, W220 S500
Even though it's running fine, I can only imagine that if it is in fact restricting the flow it would shorten the life of the pump. 140 is a good speed to find flaws though. Hahaha good luck man. I'm curious to know if a new hose will fix your issue.
Thread Starter
Senior Member
Joined: Sep 2014
Posts: 320
Likes: 87
From: Tampa
'01 CLK 430 cab, '04 SL500 (230K miles)
Replaced that hose, no change. Put in a new Mercedes fuel filter and the howl is gone. I guess the new Mann filter I put in a few months ago was bad. I would never think a fuel filter would cause this, but I understand there is also a pressure regulator in there as well.
Senior Member
Joined: Jun 2013
Posts: 287
Likes: 5
From: New Hampshire
Magma Red W208 55 AMG, W203 C230 Kompressor Sedan 6speed M/T, W220 S500
Glad you got it squared away. I'm sure someone will run into this problem and can use this to help solve it. Good job, sir.
Member
Joined: Nov 2001
Posts: 240
Likes: 2
2001 CLK 55 AMG
Thanks for posting this. It started happening to mine a few weeks ago and, from inside the car, it sort of sounded like a stuck horn. I thought it might be the fuel pump so I'm happy to hear it might just be a fuel filter.
Trending Topics
Newbie
Joined: Oct 2023
Posts: 1
Likes: 1
W202 C240
I had exactly the same problem. What was weird is it started making that noise a day after changing the fuel filter. It was KolbenSchmidt. I changed it to Mahle, and the noise disappeared. It seems the filter was either defective or fake.
MB World Stories
The Best of Mercedes & AMG
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
