lumpy 350i

[dellyend1]

Hi All,
sneaked a blast in the 350i whilst the sun was out and had a very lumpy engine at low revs to start with. Fired up and idled fine and I let it warm up properly and then put my foot down, seemed rather hesitant up to 2500 revs and then was like it cleared it's throat and was off !!

Got better the longer I was driving so suspecting moisture in engine bay, on leads etc as it has not been used for about 8 weeks.

I've done a PH search but the google facility is not coming up trumps, so any easy and quick checks . I'm thinking new leads and coil anyway as I don't know the age of them since I purchased last year

What is the preferred coil, is there one that provides a better spark etc ?

With Thanks

Jeremy

[jon haines]

I have this in my 350 all the time after it has been laid up for a period of time. they dont like not being used. it needs some spirited driving to clear its lungs and warm everything up then it should be ok.

[Danny Hoffman]

Hi,

I've had this too occasionally, finally narrowed it down to a fowled spark plug. Next time it happens try pulling of the plug leads one at a time with the engine running to find the culprit.

Danny

[MarkS1966]

I have this every time after its been more that 2 weeks since I take my car out!
As Jon says earlier, they don't like not being driven

[adam quantrill]

As the chaps say above - but if it persists, look at the ignition timing, particularly whether the advance mechanisms are working.

[pasogrande]

How old is the petrol in the tanks?

Wilf.

[350zwelgje]

Have a rising rate fuel pressure regulator and with the wedge standing for over a week, it takes 10-15 seconds to bring up the fuel pressure to what it needs to be. Until then the standard engine is lumpy, but perfect afterwards. From past experience: It runs lumpy all the time when the fuel pressure is too high....
Based on this and the ignition route not solving it, it could be worth to check/investigate next.

Rob