Cold Start Gremlin!

[Slideways]

None of the RealOEM diagrams show the correct non-CSL E46 M3 dipstick.

The SMG crankcase vent hose is shorter (and takes a different route) than the manual version due to the SMG pump being between the intake manifold and oil pan.

I thought that was a drain for the airbox, but the description for that part is "crankcase breather hose". Someone might need to verify this, but I believe it takes the positive crankcase pressure and draws it up into the intake.

If you want to know how the rest of the PCV system works for the early and later cars, there is a good discussion in this thread - https://nam3forum.com/forums/forum/m...her-tube/page2

[ac427]

How important is vacuum on when running CSL software in your DME?

The brake servo/booster obviously needs vacuum but apart form that?

[ATB88]

Thanks very much.

So is that the SMG hose in the picture in post number 40 ?

I *think* so.

EDIT: wait no. realoem says that that's the one for manual transmissions, see part number on this diagram: https://www.realoem.com/bmw/enUS/sho...diagId=11_2996

the diagram is a little misleading about how the pipes look, google the part number 11617831930

contrast with the one that realoem says is for SMG, on this diagram: https://www.realoem.com/bmw/enUS/sho...diagId=11_2999 , part number 11617831336

I think the 6MT one has that extra thing built into it whereas the SMG one doesn't. I think that whatever the function of that extra bulge on the 6MT part is, is taken care of in the rest of the different plumbing that the SMG hose plugs into?

[ac427]

FYI the part you guys are talking about is different for factory manual cars vs SMG/converted cars. I can't remember all of the details but I remember back when I was replacing that hose after I did my manual conversion it was confusing. The version of that hose for manual cars won't work for SMG and vice versa, I think the brackets/receiving ends/plumbing are a little different in either case, I think to account for getting around the SMG pump.

Thanks very much.

So is that the SMG hose in the picture in post number 40 ?

[ATB88]

FYI the part you guys are talking about is different for factory manual cars vs SMG/converted cars. I can't remember all of the details but I remember back when I was replacing that hose after I did my manual conversion it was confusing. The version of that hose for manual cars won't work for SMG and vice versa, I think the brackets/receiving ends/plumbing are a little different in either case, I think to account for getting around the SMG pump.

[ethan]

Thanks Mate. Is there a check valve in the line?

Yeah, otherwise your crankcase wouldn't be forced to vent through the cyclone separator up top.

[ac427]

There’s no connection to the dipstick, there’s a male bung threaded into the oil pan.

Thanks Mate. Is there a check valve in the line?

[bmwfnatic]

There’s no connection to the dipstick, there’s a male bung threaded into the oil pan.

[ac427]

I have a 2002 M3 manual
according to RealOEM, it's up to 09/2004 for manual vehicle.

https://www.realoem.com/bmw/enUS/showparts?id=BL93-USA-11-2001-E46-BMW-M3&diagId=11_2996

Regarding the vacuum line to FPR, yes I will be replacing with brand new silicone hose. The existing BMW design has a barb and a small U-shape tube that always fell off and ended up dangled or lost.

Thanks, I just don't think the diagram is right for my 09/2003 Convertible.

I've got an actual picture on my phone but do you think i can get it to upload. I'll have a go when I get back.

[Edit]

[ethan]

You might be right but i am wondering about a line feeding into the dipstick tube which I am i don't have.
It was a while ago but I have tried the CSL and then gone back to a standard dipstick.

Neither my stock M3 nor my CSL airbox one with CSL dipstick has a line connecting to the dipstick, but my 330xi had one stock. The M54 PCV system which, unlike the S54's cyclone separator, is external to the engine and lives underneath the intake manifold, has a cyclone separator which drains oil back to the pan by way of the dipstick.

Seems like the M3 dipstick part number (11437832140) doesn't have that plug, but the M54 one (11437531260) does. Looks like the euro M3s use the same tube as the US ones. Dunno.

Edit: I wonder if the picture shows that connection, but it actually connects to the oil pan directly because they're effectively doing the same thing and they figured it wasn't worth revving the document.

[y2k_o__o]

Thanks for all the info. I've seen the diagrams that show the a connection to the dipstick tube but i am pretty sure i don't have that on mine. Perhaps it is not on the Euro cars.
I do have a shorter plastic pipe that fits into the bottom of the CSL airbox. It looks a lot like the leftmost pipe in you picture but it is much shorter.
The NORMA elbow connector for the bottom of the airbox is the same as the ICV to additional air line connector. There are reasonable cheap still from BMW.
When you say you are replacing the vacuum line to the fuel pressure regulator. Are you going to run a new line the length of the car or just replace the rubber elbow at the back of the airbox?
Here is a link to a pic of the standard dipstick. I cannot see where the pipe would plug in: https://www.ecstuning.com/b-genuine-...e/11437832140/

I have a 2002 M3 manual, according to RealOEM, the airbox-to-dipstick hose #3 is only up to 09/2004 for manual vehicle.
For the crankcase ventilation pipe, in early model like mine, it's just a piece of tube with two Norma elbow like below picture #2. The later model after 2004 has a more complex design

https://www.realoem.com/bmw/enUS/showparts?id=BL93-USA-11-2001-E46-BMW-M3&diagId=11_2996

Regarding the vacuum line to FPR, yes I will be replacing with brand new silicone hose. The existing BMW design has a barb and a small U-shape tube that always fell off and ended up dangled or lost.

[ac427]

I rebuilt that hose with aftermarket material for my build, and I set the orientation of the check valve to allow flow from the airbox down to the crankcase. I think you're suggesting that's backwards, but it's my understanding that this line is actually an oil drain which returns oil falling out of suspension from the CCV output back down from the airbox to the crankcase. Would appreciate it y2k_o__o if you could check the direction of your factory hose's check valve before installation so I can make sure I have it right. Thanks!

You might be right but i am wondering about a line feeding into the dipstick tube which I am sure i don't have.

It was a while ago but I have tried the CSL dipstick and then gone back to a standard dipstick.

[ethan]

Crankcase vent pipe to the bottom of the airbox.

I rebuilt that hose with aftermarket material for my build, and I set the orientation of the check valve to allow flow from the airbox down to the crankcase. I think you're suggesting that's backwards, but it's my understanding that this line is actually an oil drain which returns oil falling out of suspension from the CCV output back down from the airbox to the crankcase. Would appreciate it y2k_o__o if you could check the direction of your factory hose's check valve before installation so I can make sure I have it right. Thanks!

[ac427]

These are the 3 airbox hoses I am replacing with Genuine BMW parts. Along with airbox hoses replacement, I am replacing the SAP line too since it's not hat expensive as well as the fuel pressure regulator line since they always fell off from the air rail.
From what I've read from forum, many people are having problems with airbox-to-dipstick hose ( the very far left in the picture, PN# 11617831930) since they are the flimsiest.
Since I am taking all the old hoses out, I will be replacing all the o-ring at the NORMA connector and replace all the plastic tubes with fuel hoses as spare parts. (which I already have doen for oil catch can / PCV hoses). The culprit are the thin-wall material tubes will crack under thermal cycles. The connectos are fine.
and I don't want to pay $400+ USD in the future again for these cheap plastic parts that won't last



At this point, I am taking my time to gather the technical drawing from NORMA / internet so I know which correct viton o-ring size I am replacing

Thanks for all the info. I've seen the diagrams that show the a connection to the dipstick tube but i am pretty sure i don't have that on mine. Perhaps it is not on the Euro cars.

I do have a shorter plastic pipe that fits into the bottom of the CSL airbox. It looks a lot like the leftmost pipe in you picture but it is much shorter.

The NORMA elbow connector for the bottom of the airbox is the same as the ICV to additional air line connector. There are reasonable cheap still from BMW.


When you say you are replacing the vacuum line to the fuel pressure regulator. Are you going to run a new line the length of the car or just replace the rubber elbow at the back of the airbox?

Here is a link to a pic of the standard dipstick. I cannot see where the pipe would plug in: https://www.ecstuning.com/b-genuine-...e/11437832140/

[y2k_o__o]

Thanks. Which 3 lines are you thinking of?

I know of the following pipes:

• Air shut off valve from the top of the airbox.
• OIl separator pipe from the top of the engine.
• ICV feed from the bottom of the airbox.
• Crankcase vent pipe to the bottom of the airbox.

Did you mean the brake servo/booster lines and air shutoff valve setup?

Are you measuring your LTFT through INPA ?

These are the 3 airbox hoses I am replacing with Genuine BMW parts. Along with airbox hoses replacement, I am replacing the SAP line too since it's not hat expensive as well as the fuel pressure regulator line since they always fell off from the air rail.
From what I've read from forum, many people are having problems with airbox-to-dipstick hose ( the very far left in the picture, PN# 11617831930) since they are the flimsiest.
Since I am taking all the old hoses out, I will be replacing all the o-ring at the NORMA connector and replace all the plastic tubes with fuel hoses as spare parts. (which I already have doen for oil catch can / PCV hoses). The culprit are the thin-wall material tubes will crack under thermal cycles. The connectos are fine.
and I don't want to pay $400+ USD in the future again for these cheap plastic parts that won't last



At this point, I am taking my time to gather the technical drawing from NORMA / internet so I know which correct viton o-ring size I am replacing