Need help...rough idle...whistling noise
03-13-2013, 01:17 AM
#1
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2011 E550 Coupe, 2002 CLK55 AMG
Need help...rough idle...whistling noise
Hey guys...its been a while 
I have searched high and low for an answer...but nothing.
I have a rough idle and a whistling noise coming from the area around the MAF. I would have bet my left nut that it was a vacuum leak (explains the rough idle)...but then I noticed that it makes that whine with the car off and key in position 2. Next thought based on sound makes me think noisy fuel pump (much like the performance pump i had on my race car) but Im pretty positive that the fuel pump is nowhere near the MAF, and probably located in tank or near it. Any input would be greatly appreciated...
Thanks,
Chris
I have searched high and low for an answer...but nothing.
I have a rough idle and a whistling noise coming from the area around the MAF. I would have bet my left nut that it was a vacuum leak (explains the rough idle)...but then I noticed that it makes that whine with the car off and key in position 2. Next thought based on sound makes me think noisy fuel pump (much like the performance pump i had on my race car) but Im pretty positive that the fuel pump is nowhere near the MAF, and probably located in tank or near it. Any input would be greatly appreciated...
Thanks,
Chris
03-13-2013, 05:13 PM
#2
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02 clk 55, 13 GL 450
Hey guys...its been a while
I have searched high and low for an answer...but nothing.
I have a rough idle and a whistling noise coming from the area around the MAF.
Have you tested the area with spray to see if the idle changes?
I would have bet my left nut that it was a vacuum leak (explains the rough idle)...but then I noticed that it makes that whine with the car off and key in position 2.
Hot or cold? are you sure your not hearing the air pump that runs on start up?
Next thought based on sound makes me think noisy fuel pump (much like the performance pump i had on my race car) but Im pretty positive that the fuel pump is nowhere near the MAF, and probably located in tank or near it. Any input would be greatly appreciated...
Your right that the pump is no where near. It's back by the passenger half shaft.
Thanks,
Chris
I have searched high and low for an answer...but nothing.
I have a rough idle and a whistling noise coming from the area around the MAF.
Have you tested the area with spray to see if the idle changes?
I would have bet my left nut that it was a vacuum leak (explains the rough idle)...but then I noticed that it makes that whine with the car off and key in position 2.
Hot or cold? are you sure your not hearing the air pump that runs on start up?
Next thought based on sound makes me think noisy fuel pump (much like the performance pump i had on my race car) but Im pretty positive that the fuel pump is nowhere near the MAF, and probably located in tank or near it. Any input would be greatly appreciated...
Your right that the pump is no where near. It's back by the passenger half shaft.
Thanks,
Chris
03-13-2013, 08:41 PM
#3
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Join Date: Nov 2007
Location: Huntington Beach
Posts: 16
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2011 E550 Coupe, 2002 CLK55 AMG
Unfortunately...no codes to pull. Runs like a champ except for the noise and rattle. I am doing motor/tranny mounts this weekend...maybe that will solve the rattle, but the noise is driving me nuts!
