What are these components in the engine bay?
Thread Starter
MBWorld Fanatic!
Joined: Aug 2011
Posts: 3,428
Likes: 288
From: New Zealand
What are these components in the engine bay?
What is this? It has a coolant hose running into it and appears to go into the cabin. Perhaps some sort of heater valve?
What is the black plastic thing with the blue arrow?
What is the sensor with the red arrow?
Is the yellow pointing to the air pump system? What does this do?
Thanks all.
What is the black plastic thing with the blue arrow?
What is the sensor with the red arrow?
Is the yellow pointing to the air pump system? What does this do?
Thanks all.
Super Member
Joined: Mar 2010
Posts: 684
Likes: 14
From: Lebanon
2007 BMW 550i
first of all sick engine bay 
love the color of the engine cover.
1. Red arrow in the first pic:
I think but am not sure that it is a heater valve, its not on European models; not sure why.
2. Red arrow in the second pic:
I'm not sure about that one, but its most probably an oil sensor of some sort.
3.Yellow arrow:
That the secondary air pump (emission related)
4. Blue arrow:
Not sure exactly where the arrow is pointing but the black plastic cylinder with all the 2 vacuum lines in the top is related to emissions, guess its some type of valve, if your talking about the ribbed plastic that goes down next to the arrow then that's the ground that connects to the alternator.
love the color of the engine cover.1. Red arrow in the first pic:
I think but am not sure that it is a heater valve, its not on European models; not sure why.
2. Red arrow in the second pic:
I'm not sure about that one, but its most probably an oil sensor of some sort.
3.Yellow arrow:
That the secondary air pump (emission related)
4. Blue arrow:
Not sure exactly where the arrow is pointing but the black plastic cylinder with all the 2 vacuum lines in the top is related to emissions, guess its some type of valve, if your talking about the ribbed plastic that goes down next to the arrow then that's the ground that connects to the alternator.
Junior Member
Joined: Mar 2012
Posts: 62
Likes: 10
From: Central Michigan
(2) 2004 Mercedes Benz CLK500, (2) 2005 ML500, SL500
In the 1st pic, this is a auxiliary water pump (2038350164). It pumps warm coolant through the windshield washer reservoir, for heated washer fluid on cold days.
Thread Starter
MBWorld Fanatic!
Joined: Aug 2011
Posts: 3,428
Likes: 288
From: New Zealand
Thanks for the help and engine bay compliment. I am trying to work out what is necessary and what can be removed (with the help of STAR). Yes thats right the blue arrow is supposed to mean all that black plastic stuff attached to the bracket. I saw someone had a centrifugal supercharger bracket mounted there and I was wondering how they got around removing it.
I believe the secondary air pump is for pumping oxygen into the exhaust to help a better burn when cold. Is this correct? Stupid question but does secondary mean there is a primary one also?
I believe the secondary air pump is for pumping oxygen into the exhaust to help a better burn when cold. Is this correct? Stupid question but does secondary mean there is a primary one also?
Super Member
Joined: Mar 2010
Posts: 684
Likes: 14
From: Lebanon
2007 BMW 550i
that's true about the pumping oxygen, not sure why its called secondary (dont know of a primary) but good question.. Removing any of those valves completely would result in CEL, i have experience with this as i had a couple vacuum lines that were cut and caused random codes on STAR. it is possible to relocate the valves i'm sure; they just snap into place.
