Hi, I just got this weird hissing sound as if air is leaking somewhere. Listen carefully and you'll hear air leaking/hissing sound? and then as the engine warms up. Another weird noise occurs. See second video for the weird noise.


and then as the engine warms up. This weird noise occurs. (Video 2)


I got no CEL lights just yet. Any ideas what's wrong?

 

Any sort of air leak after the mass airflow sensor would cause a CEL or stumble at idle, more severe leaks would cause the car to come close to stalling or stall.

Have you had any service in the past month or so? If so, on what?

Have you checked the belt drive components for wear, belt condition? Is there oil in the car, and does the turbo have any play in the bearings?

If the sound seems to be coming from the back of the engine bay check the vacuum lines to the wastegate control solenoid under the intake manifold. The lines become weak, swell and fall off fittings if/when they are exposed to oil.

 

With the engine running try removing you oil filler cap and see if there is a lot suction. If there is strong suction your CCV which is made into the valve cover is probably leaking. One source of the screeching noise is air being sucked in around the crank seal.

 

Crud, I jinxed myself. Had the CCV in our MINI fail last night, but since I replied to your post I did the check on mine. Here is my video

VIEW IT

I found the red diaphragm missing on the inside of the cover. Here it is on the new cover. That means its in the engine somewhere...I hope it is deteriorated enough that it doesn't clog up some oil passages.

 

Wow, mine does this too. I feel that an expensive fix is coming. How much did it cost you to fix it and what parts were needed?

 

Shoot! This just started yesterday on my R56!! Check engine light came on saying reduced emissions...

This is what it sounds like. I have the same question as preme123, how do I fix it. My guess is that I need a new valve cover. Am I correct?

Thanks

 

I see from other posts that it might be possible to clean out the junk that could be causing the vents to stick. Has anyone had luck with this. I really don't want to plunk down $350 for a new valve cover if I don't have too. Although, it's had high oil consumption since I bought it at 100K, now has 107K. I have thought that was the problem since I got it.

 

The noise in the second video made me cringe, but the first video I'm pretty sure my N18 makes that sound, only on a cold start until it gets down to about 800-900 rpms at idle. It stops after that. No CEL or loss of power on my end either.

On another note, I thought N18's couldn't use aftermarket intake pipes because of some new sensor on the part of the hose just before the turbo?

 

themrethank, did you take a look at my vid? What did you think?

 

I'm not really sure. I haven't experienced pressure like that from the oil cap. I'm not sure how different the N14 is to the N18 either

 

Any ideas on this? Will I need to buy a new valve cover or can I clean it with solvent or gas?

 

My experience with BMW engines that make that noise in the 2nd video it is air being sucked in through the crankshaft seal.

Its easy enough to pull the valve cover and look for the red diaphragm. Mine was missing! I pulled the oil pan looking for it and fond it wedged in the oil pump sprocket cover. When I took a close look at it is was soft and mushy.

 

The rubber diaphragm gets soft over time from the oil and fails to make an airtight seal, or in my case just falls out.

 

[QUOTE=Semaphore;4174033]Shoot! This just started yesterday on my R56!! Check engine light came on saying reduced emissions...

This is what it sounds like. I have the same question as preme123, how do I fix it. My guess is that I need a new valve cover. Am I correct?

Thanks

Pull your valve cover off and inspect the diaphragm on the underside and see if it is form/tight or if it has fallen out. From looking at mine I didn't see any gunk inside the passages, so doubt cleaning would do anything.

 

[QUOTE=grussell;4174219]Thanks, I'll pull it tonight and take a look.

 

Wow that is scary... I guess I'll have to check out mine as well just for the hell of it!

 

I'm not sure about the intake pipe, but I got them from Forge motorsport and been told its specifically made for the n18 engines. No problems for me whatsoever. Oh or could it be that I have a uk spec N18?

 

Pulled the valve cover and unfortunately no smoking gun... On the good side the rubber diaphragm seemed to be in good shape. I checked the other 2 flappers i could see in the vent tubes and they seem to be working fine.

Any ideas? Try and clean it out, or bite the bullet and buy a new cover? I'm thinking the latter....

 

After poking around is seems clear the valve cover needs to be replaced.

Thanks everyone for the help.

 

Updates, So I didn't have time to fix it yet. I've driven around 400miles, Both city and urban. And this morning when I was about to merge onto the main road my car sputtered and struggle to move. It then had a really rough idle. I have tons of white smoke comming out the exhaust. The OBD2 says Cylinder 1 Misfire...

I'll get it towed next week... :( sounds expensive to me.. You guys should really get it fixed before this happens!

 

Black smoke is unburnt gas, blue smoke burning oil and white smoke coolant. Sounds like you're burning coolant, ouch! Head gasket maybe.

 

Oh man sorry!!! I hope its an easy fix for you.

I replaced my valve cover gasket tonight and it seemed to do the trick.... no more crazy vacuum pressure! Cant't clear the code though, any ideas.....

 

Code cleared after a few re-starts. Still getting a temporary code when I get on it... thats super frustrating!!

 

What code did it throw? I had the fuel pressure too low code randomly and also cylinder 1 misfire.

 

I can clearly hear air leaking out of your valve cover long before you remove the oil cap, I have never heard of an original valve cover lasting 100,000 miles and 8 years, it just doesn't happen. Might as well replace the oil cap while your at it.