Hi Guys,

I was removing the air intake and I accidentally snapped the smaller of the two lines attached to it. I believe it is a vacuum line (It was extremely dry and brittle). I have searched numerous places on this forum and other BMW ones, however I cannot seem to find a consistent and definitive answer.

Can anyone tell me what specifically this is for and where it goes? How hard is it to change? Is there a part number for this? I cannot find it anywhere.

Also, I have a check engine light and got it scanned at Autozone. I am getting the following codes:

P0031 HO2S Heater Control Circuit Low (Bank 1, Sensor 1)
P0051 HO2S Heater Control Circuit Low (Bank 2, Sensor 1)
P0037 HO2S - 12 (Bank 1 Sensor 2) Heater Circuit Low Input
P0057 HO2S Heater Control Circuit Low (Bank 2, Sensor 2)

Could these codes be related to the broken vacuum line? It is such a thin line and I have read on numerous BMW forums that people drive with it removed all the time, so I did not think it would cause a check engine light.

Thanks!

The codes have nothing to do with the vacuum line.
The O2 sensors have a heater inside to bring them up to operating temperature quicker and those codes refer to a problem with the heating circuit, in your case a low voltage is being reported. The fact you have all four O2 sensors giving the code is unusual and could be down to a common earthing issue somewhere.
Each sensor will have 4 wires and generally the two wires of the same colour (e.g. black) will be the heater circuit. There should be 12V across them with the ignition on.
The heaters have no real effect on running other than warming the O2 sensors up quicker to enter closed loop quicker.

I don't know off hand what vacuum line you are referring too but any vacuum line that is compromised could lead to a lean condition (might be dependent on a valve opening so not leaking all the time) which will mean more fuel added to compensate for extra air being sucked in.
You can run with a small vacuum leak no problem but you are just burning more fuel for no reason.
Watch the short term and long term fuel trims while it's leaking and when it's plugged, if it is a vacuum leak you'll see a difference.

hi just had same problem changed thermostat to 80 deg and found broken small pipe leading to intake. repaired with pipe from fish tank . car is running better than ever as i have lpg she was throwing up eml when on lpg ond would cut out on hot restart had to keep foot on pedal . since pipe repair light is out and no stalling whatsoever i have been running like this for over a year and could not find problem . car is running great so i would def fix it . fish aint to happy though

Mine came with the pipe spigot broken and stuck with messy mastic. Got a replacement complete intake hose from a car breakers for £15 earlier this year.

I broke mine doing the thermostat mod. Fortunately there was enough left to refit the vacuum line. Ron B. VK2OTC
2003 L322 V8 Auto
2007 Yamaha XJR1300
Previous: 1983, 1986 RRC; 1995, 1996 P38A; 1995 Disco1; 1984 V8 County 110; Series IIA

I believe it goes to the PCV valve at the back of the engine, have a bit of a google but you definitely want it connected without leaks

Thanks for all of the replies.

Is it possible this is the line?:

https://www.ecstuning.com/b-genuine-bmw-pa...321437692/

No it's not...

Number six on here I believe, goes to the vacuum pipes at the rear of the head...




BMW part number 11611436644 (probably cheaper than a JLR part)

:thumbsup:

Admin note: this post has had its images recovered from a money grabbing photo hosting site and reinstated  Pete

__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Good to know Rik, thanks!

I actually just realized not only is the line broken, but the part of the line that connects to the air intake hose is leaking heavily. After taking a closer look at the air intake hose I realized that lower nipple (going to the thinner line) on the hose was broken off. The only thing connecting it to the vacuum line is a red WD-40 straw that fits in the hose and the line I think that could explain the fact that since I picked it up a couple of months ago it always stalls (the first time I start it up after it has been sitting) unless I lightly press the gas pedal to keep the rpm's up for the first 5 -10 seconds.

rik wrote:

hi just had same problem changed thermostat to 80 deg and found broken small pipe leading to intake. repaired with pipe from fish tank . car is running better than ever as i have lpg she was throwing up eml when on lpg ond would cut out on hot restart had to keep foot on pedal . since pipe repair light is out and no stalling whatsoever i have been running like this for over a year and could not find problem . car is running great so i would def fix it . fish aint to happy though

Haylands, I believe #6 is the thicker vacuum line coming off of the air intake hose.

See picture below. I think you are referring to the green and I am referring to the yellow which appears to be BMW Part Number 13321437692.

Haylands wrote:

No it's not...

Number six on here I believe, goes to the vacuum pipes at the rear of the head...




BMW part number 11611436644 (probably cheaper than a JLR part)

Admin note: this post has had its images recovered from a money grabbing photo hosting site and reinstated

deleted

Oh right, I'll shut up then... Pete

__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

Not necessary! That diagram only shows one line anyway, so it is very misleading

had a look under my bonnet and number 6 on the diagram above is the larger red vacuum pipe that connects to the vacuum hoses at the rear of the engine as shown and the small vacuum pipe goes to the back of the engine, around to the right and eventually disappears behind the coolant valve / auxiliary coolant pump or into the inner wing.

Click image to enlarge

Click image to enlarge

Jeez, you'd better finish the job! Rip off the wheel and wheelwell liner and follow that line!  Ron B. VK2OTC
2003 L322 V8 Auto
2007 Yamaha XJR1300
Previous: 1983, 1986 RRC; 1995, 1996 P38A; 1995 Disco1; 1984 V8 County 110; Series IIA