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.
SL65 strange sound when letting off the throttle (VIDEO)
Whenever I let off the throttle quickly/sharply, I get a strange noise that sounds like a dying goose for lack of better words. If I let off the throttle slowly, I get the normal whoosh noise from the BOVs without the strange noise.
Any idea on what's causing this? I do have the Speed Driven BOVs and open filter intakes.
That's a very unorthodox way to drive (mashing the throttle with no downshift then suddenly letting off before the boost kicks in?), but that sounds like it's the BOVs trying to cope with a sudden drop in throttle at low boost (higher boost = more air = the higher-pitched, more "normal" sound).
Thanks for responding. Obviously I don't regularly drive that way but I was just trying to demonstrate the noise that it makes in a controlled and repeatable fashion. It does happen during regular driving as you'd normally take your foot off of the accelerator quickly instead of easing off of it slowly when coming to a stop. Is this normal normal behavior for this engine or is this something amiss here?
It does happen during regular driving as you'd normally take your foot off of the accelerator quickly instead of easing off of it slowly when coming to a stop. Is this normal normal behavior for this engine or is this something amiss here?
I've never heard it that way, but if there's no codes and you have full boost (no boost leak/sticking valve) I don't what to say. Would have to ask the smart people ... by any chance, are you in manual mode?
It's hard to say because the "mash the throttle, but let off real fast before boost can build" driving technique he's using to force the sound is weird, too. I don't think that's a usual sound.
It's hard to say because the "mash the throttle, but let off real fast before boost can build" driving technique he's using to force the sound is weird, too. I don't think that's a usual sound.
Whenever I bought these BOVs one screw was tightened all the way down and the other was turned about 3/4 of the way down. Do these screws adjust the tightness of the spring inside the BOV? I'm pretty sure I have a picture of the day I received them, give me a minute to find it.
Whenever I bought these BOVs one screw was tightened all the way down and the other was turned about 3/4 of the way down. Do these screws adjust the tightness of the spring inside the BOV? I'm pretty sure I have a picture of the day I received them, give me a minute to find it.
No, they don't - obviously if one backed out that's not ideal.
No, they don't - obviously if one backed out that's not ideal.
This is what they looked like the day that I received them. I remember trying to tighten the one that was backed out a bit to match the one that is screwed in all of the way but it wouldn't budge and was starting to round the nut, so I just let it be.
Whenever I let off the throttle quickly/sharply, I get a strange noise that sounds like a dying goose for lack of better words. If I let off the throttle slowly, I get the normal whoosh noise from the BOVs without the strange noise.
Any idea on what's causing this? I do have the Speed Driven BOVs and open filter intakes.
Thanks for the response! Since yours does it as well with similar mods, I won't worry about it. I'm accustomed to the normal woosh noise from other turbo cars but not that particular noise in the video. Especially from a recirculating BOV that doesn't vent to the atmosphere.
08-23-2016, 04:05 PM
