What do these swirl flaps do anyway, on the later models I assume?
It could be the exhaust manifold cracked, although it doesn't sound like it. Maybe diesels and dual skin leak sound very different to petrol, which I have heard plenty of. Stainless and heat work harden and crack, cast iron or steam pipe manifolds are much better. I will check it out to see if leaking.

If it is there is a solution.
New Replacement Cast Iron Exhaust Manifold BMW X3 E83 3.0D X5 E53 3.0D Crack Fix | eBay

Do the diesels have Vanos?

The swirl flaps change the air flow into the cylinder for more efficiency. See here: -

BMW diesel engine "SWIRL FLAPS" all you ever ever need to know about Swirl flaps!

This article states that E53 with M57 variant do have swirl flaps but note what I said earlier about this. eBay vendors of don't usually list the 160kW M57TUD30 E53 as applicable for their kits.

Vanos? Nope, not on the M57D30/M57TUD30.

I know Ebay can't be trusted but it seems like every BMW is listed including 2005 E53 X5 Diesel?

6X 33MM FOR BMW DIESEL SWIRL BLANKS FLAPS REPAIR WITH INTAKE MANIFOLD GASKETS

Yeah, I've seen those too - I researched this VERY carefully when I first got my 3.0d and I have NEVER found any evidence and ANY E53 EVER got swirl flaps. Lots of folk saying that they did but no one EVER saying they had actually seen one or owned one with swirl flaps. :confused:

I'm not saying I'm right - I'm just saying I can't find any. Unicorns... and like Unicorns, they may be a mythical beast. ;)

Easy answer for you is, take a look. Pop off the acoustic cover and check for the vacuum devices the operates the swirl flaps.

No swirl flaps, the intake will look look this...

http://www.realoem.com/bmw/images/diag_2u5c.png

WITH swirl flaps, your intake will have parts 9 and 10, along with an extra vacuum port o the intake(just above 9 and 10)...

http://www.realoem.com/bmw/images/diag_35ag.jpg

There's a few extra vacuum line associated with the swirl flap control too...

http://www.realoem.com/bmw/images/diag_36cj.jpg

I'm interested to hear what you find... :D

Here's my intake - no swirl flaps. No vacuum sensor between the two acoustic cover mount points on the right rear, near the red dipstick.

http://i49.photobucket.com/albums/f2...pswgsqkt8g.jpg

You are correct Wayne, pulled the cover off and no part 9 and 10. I can rule that out. Glad I don't have these problematic things.

Do you know if the E70 ACTUALLY has them, as I will probably upgrade in a year or two?

Can't say I've looked at the E70 diesel swirl flap setup too closely, although the engine is (up until 2009) M57TU2D30, a progression of our M57TUD30 variant, so it should all be pretty familiar. After 2009 the engine is the new N57 - a whole new beasty.

Having said that, I'm pretty sure that the M57TU2D30 as fitted to the X5 (E70) does have swirl flaps, as well a DPF. But I haven't seen much bad press about them either, so maybe they are not the horror story of the earlier M57 versions that ate swirl flaps for breakfast, lunch and dinner. :yikes:

Here's a thread from this very forum showing swirl flaps on a diesel E70...

https://xoutpost.com/bmw-sav-forums/...-m57-pics.html

Lovin' my simple I6 E53!! :thumbup:

Another problem causing device is the Exhaust Gas Re-circulation System. We actually have this don't we? If so I see there is a kit to delete it. BMW X5 E53 3.0d Diesel EGR Valve Delete Bypass Stainless Steel Tube Blank Kit | eBay

If you have the M57TUD30 (and I believe you do) then you DO have an EGR. You can see it on mine in the picture I posted above - right at the very bottom of the shot, the goldish pipe connected to the inlet manifold right side (photo is from the front so left and right are swapped).

BUT, note that the kit linked in your post is for X5 2000-2003 (which is the M57D30) and doesn't mention the 2004-2006 (M57TUD30) models. That doesn't mean that the EGR is not an issue the later engines but maybe it's not such an issue, especially in our local environments (less extreme

I prefer to keep the engine stock and keep the EGR and inlet clean.
And the best way to do this is drive it lots (minimise cold running). :thumbup:

Won't the inlet be cleaner without it recirculating?