Honking noise and more - M52TU PCV, Disa?

beanie

beanie

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Hi all, I recently noticed this noise on our 2.0 M52TU. The rhythmic honking/beeping noise I assumed to be the PCV, but when revved there’s a rough, rattly sucking kind of noise.

I haven’t checked the DISA in quite a few years but I don’t remember the car making this noise before. It only seemed to happen on sharper throttle opening and not on longer, smoother openings.

youtube.com

BMW M52TU honking sound. PCV, DISA or something else?

Any thoughts on this noise? The rhythmic honking/beeping was what caught my attention but the graunching, rattly noise is also something new.Car is a 2000 BM...
youtube.com youtube.com

I’ve put this video up which is about the best I could manage!

Have I struck gold and got both things failing together, or could they be something else?
 
Best pull the Disa and have a look at the seals and flap inside, bad disa usually produce a claking sound which is different to what you have. Have you checked all the rubber vaccum hoses and intake boots to see if you have split or holes in any of these. If you cant find any then try a smoke test to see if that reveals any leaks.
 
I’ve not looked at anything yet, but I’ll have a look at the easily visible stuff before I start buying and dismantling.

With the disa, is there a preferred supplier of the rebuild kits or do most just put a new bmw one in? Assuming it needs doing of course.

Regarding parts for the PCV, is it worth paying the premium for genuine bmw bits? I’ve seen a few repair kits on eBay which include all the hoses etc but I appreciate sometimes these parts are not worth the saving.
 
I went oem for the Disa when mine started clacking on the Z3, expensive but quality assured.
Replaced my CCV system on my Z4 using a ket of parts from ebay, all fitted ok and performing as they should so far after around a year on the car.
 
I have the exact same sound coming from my z3 with the M52tub28 engine, have you found out what was causing this problem. I also have oil leaking from filter housing and would like to repair at same time if it is ccv related.
 
Thanks for the reply colb.

Kevin, I haven’t got round to it yet, thanks to the logistics of city living and cars/garages/home being awkwardly separated, but strangely haven’t heard the noise in a little while. The only thing that’s changed is I haven’t driven the car and my girlfriend never redlines it like I do!

If/when you beat me to it, please let me know!
 
Honking noise may be a collapsed oil filter, pull it out and put a good known make in it Mann filters seem to have a good name.
Also check out the Disa valve when these go bad they usually give off what is described as a clacking sound as the valve flap flutters about inside. Honking noise, my money is on the oil filter being bad.
 
Thanks, I’ll make sure it gets a decent filter. Would be nice if it’s something so simple!
 
Thanks Colbert and Beanie for your input.
Noise only started shortly after service from BMW dealership. I sometimes see small amount of oil leaking out of lid of oil Filter.
The honking sound is only audible after starting cold engine or second after switching off and goes away when warm or at higher RPM. If you lift the dipstick noise becomes very loud
I am due for a oil change with the filter housing gasket repair and am hoping it will be easier to replace.the suspected CCV at the same time without removing the manifold.
It will be fantastic if it is only a defective oil filter and not expensive Disa valve or tricky fitment of new CCV.
I have had the car for a few years and although it has literally every known Z3 problem still to be fixed from rocking seats to poor handling (wandering) in a strait line on bad roads she still runs extremely well.
Have recently purchased Meyle HD control arms , lollipops, tie rods and drop links as vague handling was my major concern, haven’t yet fitted as I need to buy a torque wrench and axel stands first.
Budget can be used for other improvements as I really want to keep this car.
 
Kevin Tyrer said:
If you lift the dipstick noise becomes very loud
Click to expand...

That is sounding more like the CCV. It is a tear in the pressure regulator diaphragm causing the noise. The pressure regulator drain goes to the dip-stick tube, so there is a direct connection for the sound to travel along.
 
You shouldn't be having oil seepage from the filter lid which makes me futher suspicious regarding the noise you hear. The oil cap lid should have a new O ring fitted each time the filter is changed same for the centre stem O rings that keep the oil from draining out of the filter housing when the engine is off. These O rings should come with the new oil filter and the lid torqued down to make the seal.
As to the CCV refresh, did my 2.5, ended up lifting the inlet manifold up and off to get the plastic pipes connected, just couldn't manage it with it still on the engine.
 
Kevin Tyrer said:
Thanks Colbert and Beanie for your input.
Noise only started shortly after service from BMW dealership. I sometimes see small amount of oil leaking out of lid of oil Filter.
The honking sound is only audible after starting cold engine or second after switching off and goes away when warm or at higher RPM. If you lift the dipstick noise becomes very loud
I am due for a oil change with the filter housing gasket repair and am hoping it will be easier to replace.the suspected CCV at the same time without removing the manifold.
It will be fantastic if it is only a defective oil filter and not expensive Disa valve or tricky fitment of new CCV.
I have had the car for a few years and although it has literally every known Z3 problem still to be fixed from rocking seats to poor handling (wandering) in a strait line on bad roads she still runs extremely well.
Have recently purchased Meyle HD control arms , lollipops, tie rods and drop links as vague handling was my major concern, haven’t yet fitted as I need to buy a torque wrench and axel stands first.
Budget can be used for other improvements as I really want to keep this car.
Click to expand...

Hi Kevin,
Some good advice from Colb and NZ00Z3, looks like a series of elimination,
MEYLE do the CCV full kit as a direct replacement (eBay), it certainly is an awkward job, however with perseverance you can change without removing the manifold.
Cheapest and easiest first option is change the oil filter, Mahle, Mann, Hengst, MEYLE are all premium quality filters, avoid lesser known or unknown brands, you will also get the o‘rings in all of the afore mentioned boxes.
 
colb said:
Honking noise may be a collapsed oil filter, pull it out and put a good known make in it Mann filters seem to have a good name.
Also check out the Disa valve when these go bad they usually give off what is described as a clacking sound as the valve flap flutters about inside. Honking noise, my money is on the oil filter being bad.
Click to expand...
Hello Colb,
you are right with your comment ‘Mann’ are a huge ‘OE’ filter manufacturer/supplier.
 
Thanks everyone for your advice. I will buy a Torque wrench and fan spanner along with filter housing gasket and CCV and attempt both at the same time as Filter and oil change.
My plan is to do everything hopefully without disturbing the manifold or breaking more things, looks easy enough on internet but aware it isn’t so easy without experience or correct tools, if I get stuck then I will have to remove the manifold.
Strangely my 98 build M52tub28 has a cable throttle and no connector pipe for CCV in the manifold so I will need to plug the outlet on the manifold pipe or better reuse old difficult twist off pipe if I can remove without breaking.
BMW parts are expensive in South Africa so need to spend limited budget wisely and will buy alternate known brands but want to avoid having to do anything again due to faulty parts
After removing throttle body,and Disa are new seals mandatory. I see a lot of tutorial videos don’t always replace.
 
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