hi i bought a 530d 2004 6 wks ago taken it back to the garage 3 times not happy with the tick over when cold, its great when warm theyve put it on a machine and nothing has come up, i manage to track down the prevous owner from new and he said it was always like that,ive just had a new manifold fitted as it was split in 5 places i thought that might be the cause of it but it aint, so what could it be.

 

MAF sensor? try unplugging it and see how the car runs. If it runs better then it may need replacing, but its not advised to leave it unplugged. (you're likely to receive an error message after unplugging it though)

 

where abouts is that and how much are they, the mechanic who done the manifold said it could be a fuel injecter and to put some diesel treatment in,

 

The MAF (part number 1):


And a real pic:


- Antti -

 

thanks, it looks like a garage job to me

 

Oh, you just need to remove the acoustic cover on top of the engine and then you have an access to the MAF. Unplug the plug, test drive and then replug it. You will possibly have an error code though. That can be solved at the dealer or some individual.

Here's the acoustic cover:


- Antti -

 

I wouldn't take it to a garage for this mate. (not if you're just unplugging it anyway)



If you do need a new part, you are better off buying a genuine bosch part instead of going to BMW as you will pay over the odds. (you can get the bosch part for around £150)

 

How long is it lumpy for? The glowplugs provide some assistance with smooth running up to a coolant temp of 30C, so a few minutes from full cold.

 

i go from my village to the nearest town which is 3 mls and its a main road so its straight up to 60mph, then its down to 30 mph, waiting in traffic lights in town it feels a little lumpy, but then i go another half mile or so to my fathers place and its ticking over fine, im not use to a big diesel as i had a xk8 which was petrol and ticked over smoothly, perhaps thats how its ment to be.

 

I have a 535d and this is exactly what I get.. lumpy first thing then fine after about 10 mins... have a few glow plug error codes too so I think I have mild problems with these and would explain the issue.. but as car starts fine I dont think its worth the expense to get them changed/looked at just for 10 mins of "lump-ish-ness" if things get worse I would consider it..