Diesel 530D lumpy running when cold

[CIS121]

That's about it - starts well, runs for a few seconds well, then it's lumpy and rough for a while. If I drive her away it's not noticeable, but is on idle and goes away after about another minute. No dashboard lights and my local garage has plugged her in and can't find any error codes. Anyone had this on their 3 litre BMW lump?
She's a 2011 530D with 90k miles, full service history - I know the last owner, he used the used the car for 70k miles and some short journeys, so I suspect this plays a part...

[Deano_BMW]

my 535d was the same when I bought it. I'm guessing its fine on warm/hot starts. the usual culprits are the glowplugs/module but as you're getting no codes you can probably (although you never should really) rule that out. The next thing is the EGR valve, and as you mention its previous usage probably hasn't helped on that score. mine was replaced and it certainly helped but didn't cure the problem in its entirety. I ultimately found out my inlet manifold was toast and had split. once a new one was fitted along with a walnut blast at the same time, the lumpiness was gone and it was as sweet as a nut.

just out of curiosity, do you get any hesitations when driving, at light throttle or if you come off and get back on the throttle? that would also potentially point to an EGR issue. you can take the cap of the end of the EGR and make sure the actuator arm is moving freely.

[CIS121]

Deano - this is great, thank you!

Even at 10C it still runs a little rough on starting so I also thought prob not glow plugs and yes, you are right on warm starts no issues.
Never had any hesitation whilst driving, but will have a look at the EGR actuator arm and also the inlet manifold as you suggest.

Thanks again!

[bigdom]

I'd be inclined to check what temperature your thermostats get to, you should see mid 90s.