ML350 ignition noise
Thread Starter
Newbie
Joined: Aug 2017
Posts: 5
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2009 GL320; 2006 E320 CDI
ML350 ignition noise
2014 ML 350 with a flex gas engine. I just replaced the plugs and the coils. The coils are the latest from Mercedes. The plug is a recommended NGK. Now I’ve got ignition noise, sounds like a sewing machine and I think it’s coming through the audio system. When I lift off the accelerator and coast, the noise stops but then resumes when I touch the accelerator again. The plugs were torqued to the factory spec. This tapping noise is driving me crazy. Any recommendations on how to track this down or what it might be other than ignition noise? I’m not throwing any codes.
thanks in advance
Ron
thanks in advance
Ron
Member
Joined: Aug 2025
Posts: 104
Likes: 20
From: Texas
2015 ML350, 2020 BMW X7, 2005 LS430
Do you think you could send a video? I had my spark plugs changed at the dealer recently for the first time at 94k miles, and after I got it changed the car started idling a little bit louder and has a loud-ish belt and tick sound, not a misfire though. Honestly it might have always been that loud but never noticed until I had the sparks and a whole lot of other work performed. Also regarding the audio system my car does have a little bit of rattle from the speakers, comes and goes occasionally but usually comes when playing music with deep lows even on low volume. Mines is the base system not the Harman Kardon. I think some plastic piece inside the speaker got loose and causing the rattle. Mines may also have the accelerator issue while driving but I wouldn't know cause my ML has a ridiculous amount of road and wind noise. I can't really help but this is just my personal experience of the sounds from my ML. I've owned the car since new, but honestly don't remember the sounds it made back then as it hasn't been driven much over the last couple years.
Thread Starter
Newbie
Joined: Aug 2017
Posts: 5
Likes: 0
2009 GL320; 2006 E320 CDI
I just completed numerous maintenance updates. The entire cooling system. Motor mounts. Cam chain tensioners and resealed the cam covers. To replace the motor mounts, I had to disconnect the engine computer. I’ve double checked all of the grounds and other connections.
