When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I've noticed a loud buzzing noise coming from the engine compartment when I turn the ignition on (engine is not started). I've used my mechanics stethoscope to track it down to some device attached to the throttle body. The sound is also loud on the Bosch unit this is attached to but I think it is the thing the arrow is pointing to. What the heck is this? I've only owned this SL320 for a month so still tracking down a number of mysteries.
You may have sorted this already. I have just had to deal with the longer term consequences of this …
A quieter version of what you are hearing is normal. The throttle body is primed and adjusts itself with motors.
If it is loud, it is a sign that the wiring look to this unit, and most probably the wiring in the Electronic Throttle Actuator/Throttle Body is on the way out. This is inevitable with the heat sink effect. I would get this replaced/refurbished as soon as you can.
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
