SL55/63/65/R230 AMG: sl65 rpm hunt when braking
Thread Starter
MBWorld Fanatic!
Joined: Dec 2004
Posts: 4,268
Likes: 253
sl65 rpm hunt when braking
today i noticed something- when i drive around normally (around town) and coming slowly to a stop my rpms hunt- not much- about 200 rpms, but they do go up, down, up, down... you can barely see it on the tach, but with the top down i could hear it clearly from the exhaust.
no codes are thrown of any kind and the car works as expected otherwise...
any ideas?
no codes are thrown of any kind and the car works as expected otherwise...
any ideas?
MBWorld Fanatic!
Joined: Apr 2006
Posts: 8,137
Likes: 26
From: Maryland
Eurocharged 2004 E500, Eurocharged ECU/TCU 2005 SL600, 2010 Caddy SwaggerWagon
Is it just when braking, or does it also do it with very light throttle?
Mine did it with very light throttle. I replaced the OEM filters with BMC and it cleared up. Sounds weird, I know....
My guess is one of the filters wasn't properly seated and changing them introduced a coicendence. Also look at the air intake tubes. There are very small mesh screens in there that become dislodged over time. Pop those bad boys out too.
The rev-hunting just seems to be a trait of these V12s. Mine still does it from time to time. I never noticed it until I removed the rear mufflers, and could hear it.
Mine did it with very light throttle. I replaced the OEM filters with BMC and it cleared up. Sounds weird, I know....
My guess is one of the filters wasn't properly seated and changing them introduced a coicendence. Also look at the air intake tubes. There are very small mesh screens in there that become dislodged over time. Pop those bad boys out too.
The rev-hunting just seems to be a trait of these V12s. Mine still does it from time to time. I never noticed it until I removed the rear mufflers, and could hear it.
Thread Starter
MBWorld Fanatic!
Joined: Dec 2004
Posts: 4,268
Likes: 253
interesting you said that. i just paid attention and noticed that it also does it around town at very light throttle ...
it is... eversoslightly jumpy...
i will remove the air boxes and inspect hoses / replace air filters
it is... eversoslightly jumpy...
i will remove the air boxes and inspect hoses / replace air filters
Super Member
Joined: Apr 2006
Posts: 796
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From: Raleigh NC
2007 E63, 2006 C55
Re: Surge
+1 on the BMC filters. Both my car and right foot love them. It idles/runs smoother at low revs when banished to puttering in stop/go traffic than with the OEM paper filters.
I do occasionally have the surge, although with my OEM "quiet" mufflers still on, it is not audibly apparent.
I do occasionally have the surge, although with my OEM "quiet" mufflers still on, it is not audibly apparent.
MBWorld Fanatic!
Joined: Jan 2011
Posts: 2,127
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From: Chicagoland
AMG
I too have this surge, totally different platform though.... Ruled out air filters. when braking, and while light throttle as described earlier. I have also noticed that when I give it wot during the jumps that the car shoots off like a bat out of an evil and cruel hell.... I love it but I find it embarrassing with passengers in the car.
