help needed with car any mechanics out there.

jewlls

hi,
i have a bmw 318, 1999, I have a problem when i start it up it idles up and down even when warm. sometimes dies out when first started up but when restarted it still idles up and down. but the car does drive fine when running until i come to stop then car starts idling again.

Any help much appreciated.

Thanks Jewlls xxxx

anewman

A dirty throttle body is a possibility. This can happen on highish mileage cars at about 100k+ miles.

peterbaker

I am only a DIYer, but until someone more knowledgable arrives, might be useful to know:
1. Diesel or Petrol?
2. Have you had any work done on it recently or is the problem completely out of the blue?

At the moment I am thinking, if diesel, and if you have also noted power hesitation at mid-revs, maybe the MAF probe needs replacement (simple if you get the right part).

Or if petrol, something similar with the lamda probe that might have been kicked off with a dodgy tank or two of petrol some months ago (remember the Tesco apology/compensation thing ... ?)


In the old days (when engines weren't managed by probes and computers) what you describe when applied to a petrol engine sounds like what was called "engine-rev-hunting" which I think was associated with a weak petrol air mixture. But that was uniquely a carburettor adjustment problem I think, and I'm pretty sure your 318 will be petrol injection i.e. no carburettor.
But it's all a bit of surmise unless you can give some further detail.

jewlls

its petrol and is mileage is 111k we had this problem a few months ago it seemed to have corrected itself on its own and over the last week it has come back with avengance, also i have just serviced the engine and slightly overfilled with the oil would this contribute to the problem, could you tell me what the throttle body is where is it and can it be cleaned.

jewlls

peterbaker

Has anewman gone off on his coffeebreak, or second breakfast perhaps!

Come back! We need to know about the throttle body angles now you've mentioned them! I think I know what a throttle body might look like, and I have even found pictures on Google but if I am right, and perhaps like the OP, I wouldn't know where to start in taking it off and cleaning it! Throttle body cleaning sounds like a Haynes 3-spanner job to me, and dunno about anewman, but they take me all weekend :think:

Andy_Edinburgh

Post on http://www.honestjohn.co.uk/forum/threads.htm?f=4

I'm sure someone will be able to guide you in the right direction.

HTH.

hartcjhart

Hi there is a really friendly BMW owners forum if you do a search on the net,

sorry cant remember the exact web address,

had a similar problem with a BM that I took in part ex apparently(from bm forum)there is a known fault(BM dont acknowledge it)with some of the slightly older ranges the cylinder liners are made from nikasel(think thats it)and it degrades with fuel or something,

any way after reading the article I have never touched a BM again

Wig

hartcjhart wrote: »

Hi there is a really friendly BMW owners forum if you do a search on the net,

sorry cant remember the exact web address,

had a similar problem with a BM that I took in part ex apparently(from bm forum)there is a known fault(BM dont acknowledge it)with some of the slightly older ranges the cylinder liners are made from nikasel(think thats it)and it degrades with fuel or something,

any way after reading the article I have never touched a BM again

And lets not forget the turbos on 320D BMW that break at a cost of £7000 repair bill and BMW doesn't give a @*** about the customers it happens to.

Wig

This BMW is doing "searching" on the idle, it might be the lambda sensor related, it might be idle valve related. I don't know.

cleaning a throttle body is easy, remove black airintake duct, take cloth dipped in petrol open butterfly valve and clean with cloth. It could be dirt here causing the butterfly to be completely closed and then putting more work onto the idle valve, but theoretically the idle valve should compensate. (which it is doing but it is searching and not coming to an equilibribrium) as I say I don't know.

harveybobbles

Wig wrote: »

And lets not forget the turbos on 320D BMW that break at a cost of £7000 repair bill and BMW doesn't give a @*** about the customers it happens to.

£7000?!?!?! WHERE?!?!

It costs about 500 quid job done!! We do em all the time!!

hartcjhart

so Wig was overcharged but you have just confirmed his/her statement about the common problem
'we do them all the time'