??? 2008 E320 Bluetec, blow off valve not holding?
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2008 E320 Bluetec
??? 2008 E320 Bluetec, blow off valve not holding?
I've recently started noticing, when I'm driving with the windows down (rarely did I do this until recently), that I can hear the turbo spool.
What I'm questioning, is whether or not the blow off valve is holding until the right pressure, as I can almost immediately hear the valve open at low rpm and low load.
1) I don't remember ever hearing the turbo nor the BOV previously (I've owned the car for 5 years)
2) If I can hear the BOV open/whistling, shouldn't it be more like a normal BOV, where I can here the psshh when I let up on the gas?
Thanks for any thoughts.
What I'm questioning, is whether or not the blow off valve is holding until the right pressure, as I can almost immediately hear the valve open at low rpm and low load.
1) I don't remember ever hearing the turbo nor the BOV previously (I've owned the car for 5 years)
2) If I can hear the BOV open/whistling, shouldn't it be more like a normal BOV, where I can here the psshh when I let up on the gas?
Thanks for any thoughts.
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2008 E320 Bluetec
Hmm.. Now I'm reading that diesels don't have BOVs?
If not, am I hearing the wastegate of the turbo, perhaps through a crack in the exhaust manifold or exhaust?
Does anyone else hear their turbo spool and a high pitched wind sound from their bluetec or CDI even?
If not, am I hearing the wastegate of the turbo, perhaps through a crack in the exhaust manifold or exhaust?
Does anyone else hear their turbo spool and a high pitched wind sound from their bluetec or CDI even?
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From: USA, EU
06 E320 CDI (GONE), 14 Jeep GC EcoDiesel, 01 Disco II (GONE), 09 BMW X3 3.0 Si Xdrive
No BOV on this turbo, neither wastegate, it is VNT turbo and thus why spools quite fast at low rpm's. On any car with BOV or wastegate those will work to release the extra pressure usually at high rpm/engine load, but not at low rpm and partial to normal load.
Senior Member
Joined: Mar 2009
Posts: 430
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From: USA, EU
06 E320 CDI (GONE), 14 Jeep GC EcoDiesel, 01 Disco II (GONE), 09 BMW X3 3.0 Si Xdrive
I hear my turbo spooling all the time and I would like to say that this is normal for this type turbos. As of the air sound you may want to check for air leaks, but if you have one you will get CEL most likely because of pressure lost.
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2008 E320 Bluetec
Many years later, but you guys deserve closure..
Turned out to be the rubber charge tube between turbo and intercooler had a cut in it, and it was the air blowing out of it.
Once fixed, I don't hear the sound anymore.
Turned out to be the rubber charge tube between turbo and intercooler had a cut in it, and it was the air blowing out of it.
Once fixed, I don't hear the sound anymore.
