Whats this item called?

[steviedee]

Good afternoon.
Yr 2000 Z3 2.2.
When I have the ignition turned to position 2 (dash lights on, engine not running) I get a buzzing from this box pictured. I doubt that it should do that but I am unsure. I am investigating why I am only getting about 250 miles from a tank of fuel. So before I dive in and start probing, can some one advise what it is / does please?

 

[Paul Rice]

Looks like the Disa valve

 

[t-tony]

It is the Disa valve.

Tony.

 

[steviedee]

Ahhhhhhhh . Thanks guys! Now I can investigate further with more confidence. Ive just read that worn seals in this valve can lead to bad fuel consumption which I am suffering from.

 

[steviedee]

Right.
So I set the ignition to position 2 (dash lights on engine not running) . I get the electrical buzzing sound. I unplug the multipin from the Disa valve and its still buzzing. So its not the Disa valve. But underneath the valve is another black box (which the disa multipin connector comes from) which is doing the buzzing. I put my ear to it via a screwdriver and its definitely this box buzzing. I'm guessing stuck solenoid?
Heres a pic:

 

[the Nefyn cat]

This may help narrow it down

RealOEM.com - Select Your BMW Model

RealOEM.com BMW Parts website. This site can be used to look up BMW part numbers and approximate part prices. The Parts are grouped into diagrams and diagrams are grouped into categories and subcategories

www.realoem.com

 

[NZ00Z3]

The noise is the idle control valve humming it's merry tune. That's normal. When it stops humming with the key in position 2, then that's the time to worry as it will need a clean.

If your fuel economy is down, then you may have a vacuum leak. A common problem is a hole in a small elbow tube to the idle control valve. Follow the main air induction boot down towards the throttle body. The small elbow tube comes off on the firewall side down low. The outside edge of the corner is the usual hole place.

Scan the engine computer for codes and look at the 4 fuel trims. If any are > 8%, then you likely have a problem to find.

 

[steviedee]

I think I know what you mean. I just took a picture of the air intake boot which connects to the boot that connects to the MAF sensor (if you follow me) . Its definitely perished all the way through. I shall be replacing this right away.
As for scanning the engine codes, I have a pretty standard OBD scanner which has helped me with fault codes but it doesnt go any deeper. Not sure what you mean by the 4 fuel trims?
Whats the weather like in NZ by the way?

 

[steviedee]

 

[steviedee]

Just wanna say a quick thanks to Nefyns Cat for the parts catalogue. Very helpful so far!

 

[the Nefyn cat]

That's what we're here for, any chance to help someone spend their money.

 

[NZ00Z3]

Yes, that is the rubber part I was talking about.

You may like to update your scanner.

• An OBD2 adapter and the smart phone app called OBD Fusion is a cheap way to go for sorting engine related stuff. This thread tells you how to set it up. https://www.e46fanatics.com/threads/obd-fusion.1240733/#post-18380161
• To talk to the other modules in the car you need a scanner that talks the BMW language. Creator have a couple of cheap scanner that work well and have a following on this forum. The C110 and C310+

Your car has 2 banks of cylinders, 1 to 3 and 4 to 6. Each bank has a short term and a long term fuel trim, so there are 4 of them. The Engine computer uses the fuel trims to adjust the mixture to keep the engine running right. We can tell a lot about how the engine is running from knowing the 4 fuel trims.

The weather in N.Z. is warming up nicely. It's spring. I can see magnolia and cherry blossom out the window. Looking forward to a great summer of enjoying the Z3.

 

[the Nefyn cat]

Pah. Looking forward to a great winter of testing the heater.

 

[motco]

Pah. Looking forward to a great winter of testing the heater.

...and testing the windscreen wipers if my experience of the weather in the Lleyn peninsula is any guide!

 

[the Nefyn cat]

It's not raining at the moment.

Which means that it will soon.

 

[the Nefyn cat]

It's not raining at the moment.

Which means that it will soon.

Shouldn't really quote myself, but it's just rained, with plenty more to come from the looks of it. The wind's blowing from the West just now, which means that it'll be heading Eastwards towards the rest of the country.
Enjoy it while it lasts, there's bound to be a water shortage and hose-pipe ban coming soon.

 

[motco]

To be honest I've had some good times in sunny conditions in the mountains of north Wales. With none of the damned midges that Scotland has in spades. Early morning swimming off Dinas Dinlle in 1961 while on holiday with my parents. Meeting a pretty young lady also staying in Dinas Dinlle and exploring the derelict building at the old RAF base with her. She was from Billericay in Essex, and now lives in Canada.

 

[the Nefyn cat]

Yep, been sunburnt up here many times, didn't come here expecting a tropical paradise, but every now and again it takes you by surprise, and the roof goes down all year long. Good heaters in these Z3s.