Rough idle ( jumping revs) 1.9 1998

[jazZ3r]

Hey everyone, Just looking for some advice on a newly acquired z3. I’ve driven a few hundred miles since buying and it’s starting to really struggle with idling and general smooth cruising... I’ve looked at engine bay and can see this tube is split (see pic attached) ... would this be a culprit and what part is this?any help with this issue would be greatly appreciated! Thanks, Jack

 

[Synclare]

That's the crankcase breather pipe that should be connected to the large adjacent ribbed pipe in the picture.. Any splits in pipes will cause problems. Genuine BMW pipes aren't generally that more expensive (certainly on the 6 cylinder cars) than aftermarket pipes and better quality.
That small breather pipe goes to the camshaft cover hidden under the inlet manifold.

 

[the Nefyn cat]

If you want to be able to quote part numbers, put your last seven into https://www.realoem.com/bmw/select.do and go through the sections till you find the bit(s) you're looking for. If one hose is split, there may well be more, it happens on these. How do we know?

 

[Stevo7682]

Yes totally agree with the others comments all air intake , breather and vacuum hoses need to be intact or rough idle, rough running and poor fuel economy becomes the order of the day

 

[jazZ3r]

Thanks so much- Will look into getting this sorted!

 

[Stevo7682]

Is yours an M44 engine

 

[jazZ3r]

Is yours an M44 engine

Yeah m44

 

[Stevo7682]

Was going to post some pictures up from real oem but the various hoses are in different areas.
So here is the link to realoem
https://www.realoem.com/bmw/enUS/select

Put in last 7 of chassis number click browse parts then you can look at the various sections and get the part numbers and images for the bits you may require.