BMW Questions? Ask a BMW Repair Expert for Answers.
Hi, and welcome. My name isXXXXX noise you are hearing is most likely coming from the crankcase vent valve. When the valve fails it can cause a squeak or honking noise to come from the crankcase. If you remove the oil cap and the noise goes away it is most certainly a bad vent valve.
Another possibility would be a bad bearing in one of the belt pulleys but removing the dipstick would have no affect on a noise from the bearings. This sounds more like a bad vent valve.
when the car is idle I don't hear it
if I start it in the morning and its idle then I hear it for a few seconds then stop
Is the check engine light on?
no the engine light is off
I have no errors on the dashboard
Do you only hear the noise first thing in the morning?
Are you sure removing the dipstick affects the noise?
I hear it off and on...example if im taking off slow
yes I tested it this morning..i starting the car then I took out the dipstick and it got louder
Ok, if that is the case it would have to be a fault with the vent valve for the crankcase ventilation.
its more like a honking soft sound
how can I fix that?
It's a very common problem on the BMW and it can cause strange noises in the crankcase when it fails. A honking type of noise is definitely one of the symptoms.
r u there still?
Well first there is a test that we perform with a manometer to be sure the valve is bad. The valve is located underneath the intake manifold and is very difficult to access. The normal charge for replacing the valve and the vent hoses that connect to the valve is about 2.5 hours.
Click on the image above. Item #2 is the valve.
#4 is where the hose from the valve connects to the dipstick tube. That's why it gets louder when you remove the dipstick.
#1 is the vent hose that runs from the valve cover to the valve.
The valve retails for $87.
is there any other way I can fix temporary
Not really. If the valve is bad it will need replacing. The hoses that connect to the valve should be inspected as well. If a hose split it could cause the noise but it's usually the valve. You would need to inspect the hoses from underneath the car.
I live in the caribean
they aren't really good bmw mechanic
I can imagine.
Click here for a good article on the replacement if you want to attempt this yourself.
Or you could print the article and give it to your mechanic.
I have a question
how many questions can I ask u
the more questions I ask the more I have to pay? how does it works
If it pertains to the same problem you can ask all you want. If it is on a different problem you are supposed to open a new question. They don't like us answering multiple questions on different problems under the same question.
Just go ahead and post the question here and I'll see what I can do.
ok I understand
my ac works fine while I'm driving but when I stop it doesn't cold
Have you had the a/c system evacuated and recharged for this problem? Low refrigerant is the most common cause of poor cooling.
I would also make sure that the fan in front of the a/c condenser is working at idle.
ok I will check that out
You're welcome. If you would please take a moment to rate my service today I would appreciate it.
I just replace the vent valve and hose
And it still makes that honking noise
The mechanic change the crank case valve with a spare one that he had and still made the noise and the hoses are in good condition..
what else can be the problem. PLease let me know ASAP
he told me the noise indeed was coming from the intake manifold