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How to Replace Oil Separator Breather Hose 01-05 BMW 325 Xi

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  1. step : Removing the Air Filter Box (0:25)
    • Remove the air collector push pin retainers
    • Remove the air collector
    • Disconnect the MAF electrical connector
    • Loosen the air filter box hose clamp
    • Disconnect the air tube from the air filter box
    • Release the air filter box lever latches
    • Remove the air filter box lid
    • Remove the air filter
    • Remove the two 10 mm bolts securing the air filter box
    • Disconnect the wiring from the retaining tab
    • Remove the air filter box
  2. step : Removing the Cabin Air Filter Tray (1:54)
    • Unlock the three twist locks to release the cabin air filter cover at the rear of the engine compartment
    • Remove the cabin air filter
    • Remove the four T30 screws along the rear of the cabin air filter tray
    • Pry the tabs along the wiring retainer to remove the wiring
    • Remove the cabin air filter tray
  3. step : Removing the Oil Dipstick Tube (2:39)
    • Remove the weather stripping from the drivers side engine compartment barrier
    • Remove the twist lock to remove the engine compartment barrier
    • Remove the vacuum hose and wire from the engine compartment barrier
    • Disconnect the two hoses from the intake snorkel
    • Loosen the two hose clamps on the inner end of the intake snorkel with a 6 mm socket or flat blade screwdriver
    • Remove the intake snorkel
    • Remove the fuel line and small vacuum line from the retaining bracket near the dipstick tube
    • Remove the 13 mm bolt securing the dipstick tube
    • Disconnect the vacuum hose from the dipstick tube
    • Remove the dipstick tube
  4. step : Removing the Oil Separator Breather Hose (7:45)
    • Disconnect the purge solenoid electrical connector
    • Pull out the purge solenoid and disconnect the hoses from it
    • Disconnect the upper electrical connector from the driver side of the intake plenum
    • Disconnect the electrical connector below the driver side of the intake plenum
    • Disconnect the alternator and camshaft sensor electrical connectors
    • Remove the 10 mm wiring junction bolt
    • Remove the two 10 mm wiring junction nuts
    • Cut the wire tie securing wires to the rear driver side corner of the intake plenum
    • Disconnect the electrical connector at the rear of the intake plenum
    • Disconnect the oil separator breather hose from the crankcase ventilation housing
  5. step : Installing the Oil Separator Breather Hose (11:29)
    • Connect the oil separator breather hose to the crankcase ventilation housing
    • Reconnect the oil temperature sensor electrical connector
    • Install the electrical junction onto the mounting studs
    • Secure the electrical junction with the two 10 mm nuts and 10 mm bolt
    • Reconnect the throttle body electrical connector
    • Reconnect the crank sensor electrical connector
    • Reconnect the alternator electrical connector
    • Reconnect the electrical connector at the top driver side of the intake plenum
    • Reconnect the idle air control valve electrical connector
  6. step : Installing the Oil Dipstick Tube (13:43)
    • Replace the oil dipstick tube O-ring, if necessary
    • Make sure not to drop the O-ring into the engine if you need to remove it
    • Install the oil dipstick tube into the hole
    • Secure the dipstick tube bracket with the 13 mm bolt
    • Reconnect the breather hose to the dipstick tube
    • Reinstall the fuel line retaining clip to the dipstick tube and secure the fuel line in it
    • Reconnect the intake snorkel to the throttle body and idle air valve
    • Tighten the two worm clamps
    • Reconnect the vacuum hoses to the intake snorkel
    • Install the engine compartment barrier
    • Secure the barrier with the twist lock
    • Install the hose and wires into the barrier
    • Install the weather strip on the barrier
    • Install the purge solenoid onto the bracket
    • Reconnect the hoses and electrical connector to the purge solenoid
    • Install the dipstick into the tube
  7. step : Installing the Air Filter Box (19:21)
    • Lower the air filter box into position
    • Install the two 10 mm air filter box bolts
    • Install the air filter
    • Slide the air filter cover onto the air tube
    • Secure the air filter cover with the lever latches
    • Reconnect the MAF electrical connector
    • Tighten the air filter cover hose clamp
    • Insert the air collector into the air filter box
    • Secure the air collector with the push pin retainers

What's up guys? I'm Andy from 1A Auto. In this video I'm going to show you how to replace the engine oil separator breather hose on this 2001 BMW 325xi. If you need this part or other parts for your vehicle, click the link in the description and head over to

We're going to remove this piece. I just want to take some side cutters. Remove these push pins. Be careful not to cut them. Pull that out. Now we'll just grab this, pull this aside. There is a couple of clips on there if it's not coming out too easy, just take a straight blade screwdriver and push those in. Disconnect the mass air flow sensors, push down. Wiggle the connector off. Set that aside. Take a straight blade screwdriver, loosen up this worm clamp. Right there, just like that. We can take that snorkel off right now.

Next, I'm going to take these two 10 millimeter bolts out. You could take this top cover up first if you want to unclip it, pull that off, pull the air filter out, but I'm going to keep that all together. Use a 10 millimeter socket extension and electric ratchet. If you don't have an electric ratchet, use a regular ratchet. Loosen these up. Take those two bolts out. You can grab the air box, all as one, and just slide it up. I need to remove these wires from this housing right here. You can either take the cover off or you could slide it up right there. I like to take this cover off. Just take a screwdriver, slide that off like that. Pull that out of the way. Grab these wires, pull that down. Pull this one down.

Now I'm going to use a T30 socket extension and a ratchet and I have four screws right there. Take those off. So it's all loose. You can just slide this panel up, slide it out of your way. I'm going to take this intake snorkel off. I want to take these two hoses off right here. You can just grab them, twist them, slide it out, could use a little pick in there if you're struggling to get this off. All right, just go around like that and you should be able to twist it off. Should come off a little bit easier. And if you have hose pliers, you can use hose pliers. Always makes it a lot easier. Take that off.

So there's a hose that slides off this intake tube right here. So there's two different hose clamps that I have to remove, this one and then the one that's further in there. It's kind of hard to see. So I'm just going to take a pocket screwdriver, slide underneath here, try to get on it and loosen that hose clip. You'll be able to see it a little better once I get this snorkel out. It was actually a little bit easier to take a six millimeter socket and extension and a ratchet and loosen that worm clamp up like that. Now I'm going to put it on a longer extension. I'm going to try and get this one out. If not, I'm going to have to use a screwdriver. Use the ratchet, six millimeter socket. Try to get this to loosen up. So those are both loosened up. Just grab it, wiggle it a little bit, twist it back and forth. Make sure you don't rip it and slide it out just like that.

We want to take the dipstick tube out. There's a bracket right here that has a retainer that holds this vacuum line. And then also the fuel line right here. Just slide the fuel line out. Just pop it out like that. And then this little bracket, I'm just going to take some needle nose pliers and just pinch this together. Push it through. A little bit tricky to get in there, but there we go. Push that through. And then there's a bolt down here that's going towards the front of the vehicle. So we're going to take a 13 millimeter socket and a ratchet. If you have a flex-head ratchet, that would help out. All right, so I was able to break it free. If you struggle with this, you can try breaking it free with a wrench. It's just really tight in there. All right, so I take that bolt out. All right, so I'll just take a right angle pick, try to get in underneath it and then just go around the hose, loosen up that seal. It's kind of made a seal and that's what makes it stick to the hose.

Now that loosened, I should be a little to twist this. Yup. And pull it off. There we go. Grab the dipstick tube and just slide it out. All right, so we got the dipstick loose, what we want to do is take this cover off right here because we can't get the dipstick to slide any further up. So we'll loosen this up right here, take that off, take this weather stripping off right here, slide this up, slide this wire out of the way. Oops that fell down. Just make sure these hoses are not attached. Slide the hoses out of the way. We should be able to slide this cover back, look out for this vacuum hose right here, and it slides out pretty easily. So then you can slide the dipstick up, a little bit easier to get that out. And there you go. I would recommend taking this cover out before you started taking the dipstick out. It'll give you a little bit more room in there and it'll be less of a struggle for you.

Disconnect the connector right here. This is on the purge solenoid. You just push that little tab down right there. The connector right here, remove this connector, a little tab right there. Push down on that, slide that off, and there's another connector right under here. It's kind of hard to see. Push down on that. Slide that out. You can mark all these connectors if you want to, but they pretty much don't give you enough wire to connect them in the wrong spot, so you should be all set trying to figure out which connector goes where when you're going to put it back together. Slide that one out. And right here, there's one that goes to the alternator. Just disconnect this connector just like that. There's one more connector down here. This goes to a camshaft sensor. You can disconnect this one. I think we could probably leave this one plugged in, but we'll disconnect it anyway.

I'm going to use a 10 millimeter socket extension and ratchet. Take this bolt out right here. Then I'm going to take this nut out. Still use the same socket and ratchet. Take that nut off. Right by the throttle body, there's a another bolt, a nut that's attached. We're going to have to go under the wire or over this wire right here. Take a 10 millimeter socket extension and ratchet. Get that one out. Once you crack it free, you can loosen it by hand. Pull the nut up. Be able to slide this out, and that should be out of our way. The connector that comes from this junction block right here, junction of wires, and just follow the wire up. Disconnect the connector right there. That one right there, you just push down on that little spring clip. Now there's a little more room.

So now underneath here it's kind of hard to see, but there's a drain that comes off the crankcase ventilation housing right there. This is to drain the oil back into the oil pan, so you're just going to squeeze this tube. Once I get it out, you'll be able to see it a little better. And this connects to the dipstick tube. This was that tube that came off the dipstick. All right, pulled that off, that's the tube, you just squeeze this like that and then you can just slide this tube right down.

Here's the old part. Here's the new engine oil separator breather hose from As you can see, the shape of the part is the same. The fitting is the same on the end, has a protective sleeve on it. Get yours at and you'll be ready to rock and roll.

So this other end is going to attach to the oil dipstick tube. So keep in mind you want this in that general location of where that dipstick tube was. And then we're going to hook this to the base right here. It's just going to slide up and that's that crankcase ventilation housing. Make sure it locks in place. Now I want to reattach this piece, but just make sure any connectors you can get, plug those in. This one was to the oil temperature sensor, so that goes right there. And then once we attach this, there's a stud right here, that and there's a stud down below here. Make sure you get that bracket on the stud and then take the two nuts. There's one that goes up here, get that one started. One goes through this lower stud. Get that one on. And then we have a bolt that goes right there. Install that bolt.

Now, I'll just take a 10 millimeter socket and ratchet. Tighten this up and those other two nuts. For this lower bolt, lower nut, I just used a extension. It's kind of hard to get to, and then just snug this one up as well. And there's a crank sensor connector right here, line that up, lock that in place. This connector right here goes to the alternator. Plug that in, lock it in place. Connector's going to go right here, lock that in place. This connector goes to the idle air control valve right here. Line that up, lock it in place. Where the dipstick hole is, where it goes into the engine, there's an actual O-ring there. It's a good idea to replace that O-ring if possible. You're going to have to use a pick and try to pick it out and just make sure it doesn't fall into the engine oil pan, but ours looks okay. So I'm not going to. But you could end up with a back end leak afterwards or even an oil leak. So just keep that in mind if you're pulling the dipstick tube out.

All right, so with a new O-ring or take the old O-ring out of the engine, just slide that up there and you can lubricate this with some white lithium grease or some engine oil. Then just line this up in position. These coolant hoses kind of get in getting way a little bit, kind of got to move those out of the way. Slide that down. Just like that. All right, push that dipstick down, make sure it goes down all the way. What you could do is take a mirror and just check the bracket and make sure the bracket's lined up with the bolt hole. Sometimes that can be tricky. Just make sure you lubricate the O-ring and you should be able to get it. Now I'm going to put the bolt in. I'm just going to get it lined up.

All right, now I'm going to tighten that bolt down. I'm actually going to use a 13 millimeter swivel socket and an electric ratchet. If you don't have a swivel socket or an electric ratchet, you can use a regular one. It's just there's not a lot of room to work back here, so I'll just tighten this up, snug it down. I'll go back with a wrench, just use a 13 millimeter wrench and just snug it. You could use a ratchet wrench also. There we go, that's good. So here's the other end of that breather or the drain hose and we're going to slide that onto the dipstick tube right here. There we go, and just slide it all the way on, and that's good. Now I did take this bracket off before I put the dipstick tube on. This is just going to hold the fuel line, so I'm just going to reinstall that. Just slide that back into the bracket on the dipstick tube right there. It's kind of hard to see. And then slide the fuel line back in there.

So if these hoses got in your way, you could remove this bracket when you were doing the dipstick. So just reinstall this, slide these hoses back in, and then this will slide right over here. That's good. Next, before I install this panel right here, it is going to be significantly easier to install this snorkel. So we're going to install this now. When we took it out, we did it the other way. But it's a lot easier to get this in this. Just line this up. Make sure you're worm clamps are on there. And then from up here, I'm just going to use this screwdriver, straight blade screwdriver and tighten up that worm clamp that goes on that top port of the snorkel. Snug that up, and then do the same with the bottom one.

So we're going to take these vacuum lines. One that goes to the top, this comes right off the intake right there, and this one comes from underneath there. So install that. That's good. Now we'll take this cover, slide this over here. If you struggle with this you can pull the brake booster hose off, get a little more room, there we go. Get it lined up. So it's actually one of these push twist retainers that hold this in. So we'll just get that lined up. Push it in. Yep, so that's good. You may have one over here. This vehicle did not have one there, so keep that in mind. Now we'll take this vacuum hose that goes to the brake booster, line this up right there, reinsert it into the booster and then same with this wire. Just slide this right there. Now we can take the weather strip, get this lined up just like that.

Take the connector. This is the connector for that and lock that in place. Install the dipstick. We can reinstall the air box. Get back in position, move this clamp over here. Install these two bolts here and here. Take a 10 millimeter socket extension and ratchet. Tighten these bolts up. Just snug. That's good. Use a straight blade screwdriver, tighten up this worm clamp, snug and plug this connector in to the mass airflow sensor, lock it in place.

Take this intake, put this back through the air box, clip it in place. Take the push pins, get these lined up. I'm just going to get them all started first and then lock them down. Lock it down. All right, now we want to install this. Just get this lined up. You can get these screws started. I'm going to take a T30 socket extension and a ratchet. Tighten these up. Now reinstall these wires in this cover right here, just like that. Take this cover and line it up and it's good. Take the filter, we're going to slide it in with the curved side towards the vehicle. So the bode side more towards the out of the vehicle. Just slide that in position like that. We'll take this cover, it's going to just slide in underneath this weatherstripping. Just push it in. Get these lock tabs to line up and lock them down. They're spring loaded. And the last one, and you're good to go.

Thanks for watching. Visit for quality auto parts shipped to your door, the place for DIY auto repair. And if you enjoyed this video, please click the subscribe button.

Tools needed for replacement:

    General Tools

  • Pick

  • Pliers, Cutters & misc Wrenches

  • Side Cutters
  • Needle nose pliers
  • Pliers

  • Ratchets & Related

  • Socket Extensions
  • Ratchet

  • Screwdrivers & Related

  • Flat Blade Screwdriver

  • Sockets - Metric

  • 13mm Socket
  • 6mm Socket
  • 10mm Socket

  • Star Drivers & Sockets

  • T30 Socket

2001 - 2005  BMW  330i
2001 - 2006  BMW  330Ci
2001 - 2005  BMW  330Xi
2001 - 2005  BMW  325Xi
2001 - 2005  BMW  325i
1999 - 2000  BMW  328i
2000 - 2000  BMW  328Ci
2001 - 2005  BMW  525i
1999 - 2000  BMW  528i
2001 - 2005  BMW  530i
2004 - 2006  BMW  X3
2003 - 2005  BMW  Z4
2001 - 2002  BMW  Z3
1999 - 2000  BMW  Z3
1998 - 2000  BMW  Z3
1999 - 2000  BMW  323i
2001 - 2006  BMW  325Ci
2000 - 2000  BMW  323Ci

99-06 BMW 3 & 5 Series Engine Oil Separator Breather Hose (Vent Valve to Dipstick Breather Tube)

BMW Engine Oil Separator Breather Hose URO

This part replaces:

  • OE # 11157532649
  • URO 11 15 7 532 649
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