Oil in Intake/AirBox

[purple haze]

so been a slow month waiting on parts to arrive to AUS, but now i have finally
replaced tube of death seals
cleaned all the intake parts and vacuum lines
replaced mani gaskets
New air filter
rebuilt injectors and changed fuel filter (Thanks to Mr injector, great customer support and prompt mailing)

been driving it for the past two weeks and no oil leak and has a dead steady idle speed,
so im assuming there is no other vacuum leaks.

Thanks for the help and advice everyone!!

[purple haze]

Ok cheers il give that a go for the ps reservoir.

I'm just about to order the parts seals ect, I can't figure out what injector rebuild kit I need for the 320i, do all the Bosch injectors share the same pintle ect? The number on the injector is 0280150716

[dnguyen1963]

If you have had the injectors out already...rebuild them. As for the power steering hoses, put new clamps on both top and bottom and you should see no more leaks.

[jeffnhiscars]

The injector kit I got (from mrinjector of course) had new pintle caps, filters & orings. If you dont have that option Id try to replace that cap regardless.

Ive also found that PS reservoir leaks are often those "one time" use hose clamps and/or a bad hose end and can be easily cleaned up to not leak.

[purple haze]

New o-rings will fix any intake leaks at the oil return tube, but there are other possible leaks. Replace the valve cover gasket and the four rubber rocker shaft plugs, the oil filler cap, and the dip stick o-rings. When everything is back together, have a smoke test done.

1. Ok so i should replace?
VC gasket
Rocker Shaft Plugs
Oil filler cap
Dip stick o-rings
Do i need to worry about cam seals?

2. Little update, kind of non oil related,
was taking off the fuel rail and injectors and dropped an injector onto the valve cover and busted a pintle, i love making things more complicated for myself :sad:
might not be able to see in the pic.



What are my options, i was taking them out to clean and put new o-rings on.
should i just get new pintles and filter caps for all the injectors?

3. another unrelated to topic question.
Found the power steering reservoir inlet is leaking ATF everywhere, do i need a new hose or can i put a hose clamp and seal it?


Thanks for the responses guys.

[dnguyen1963]

I have stared pulling off the intake today, and have a few Questions.

3. Bit of a noob question but do i really need to replace the hose clamps that i have loosened?

If it is BMW crimp-style clamp then the answer is no.

[jlevie]

The metal elbows on the sides of the throttle body were pressed in. Over time they will loosen and be the cause of an intake leak. The fix is easy. Clean the nipple and bore with acetone or lacquer thinner and glue the elbow in with JBweld. Do this with everything assembled so the elbow is at the correct angle. Allow the epoxy to cure for 24 hours before running the engine.

New o-rings will fix any intake leaks at the oil return tube, but there are other possible leaks. Replace the valve cover gasket and the four rubber rocker shaft plugs, the oil filler cap, and the dip stick o-rings. When everything is back together, have a smoke test done.

Unless damaged, screw type hose clamps can be reused.

[purple haze]

I have stared pulling off the intake today, and have a few Questions.

1. noticed the the metal L pipe connecter the goes from the throttle body to the Idle control Valve tube was pretty loose and easy to get off,
do i need a new Part when i re-install there seems be be no seals for these connectors or is that normal?

2. Once i have resealed the Oil Return Tube will this eliminate vacuum seal as the problem of oil in the airbox or what other things should i check while i have the manifold off?

3. Bit of a noob question but do i really need to replace the hose clamps that i have loosened?

[jeffnhiscars]

It wont fix the cause but if you drill a small drain hole in the TPS cover it should limit the symptoms until you find the problem.

[jlevie]

a little oil film is normal, puddles and a soaked filter aren't.

Correct!

[nando]

a little oil film is normal, puddles and a soaked filter aren't.

[Quinthirty]

check the seals on the "tube of death" under the intake manifold

an oil film may me normal, but puddles is not.

for some odd reason, a big vac leak from that tube will cause oil to pool up in the intake.

Does that mean that oil film up to the black elbow boot is normal?

[jlevie]

no it doesn't connect to the intake. I don't fully understand how it can cause oil to back up into the intake manifold, but it definitely did - when I first built my motor in 2006 it sucked almost a full quart all the way to the airbox. I thought I screwed up the build, but then I found out the tube of death wasn't sealed right. Got that fixed and it went away.. that was 80,000 miles ago.

That is easy to explain. The crankcase is at less than atmospheric pressure (the intake sucks on it). An air leak at the oil return tube, or anywhere else on the block, increases the airflow from the block into the intake. Which drags more oil vapor into the intake. There are several places other than the oil return tube to have leaks and a smoke test is the way to find them.

[Northern]

Possibly coming from pcv? Both my m20s have a small amount of oil in the tb that I assume is from this.

[nando]

no it doesn't connect to the intake. I don't fully understand how it can cause oil to back up into the intake manifold, but it definitely did - when I first built my motor in 2006 it sucked almost a full quart all the way to the airbox. I thought I screwed up the build, but then I found out the tube of death wasn't sealed right. Got that fixed and it went away.. that was 80,000 miles ago.

The o-rings will need replaced, there's one at the top and one at the bottom. probably worth redoing all the intake manifold gaskets while you're at it, and possibly having the injectors rebuilt/serviced.