630i N52 Starter rough idle problem Help!

[Sixy]

Hi all. Have a 2008 N52 630i that ran like a dream until the starter died. I disconnected the battery, removed the intake manifold and replaced the starter. Reconnected the battery and she started like dream. But... it runs like a sack of spuds! Very rough idle with multiple fault codes, cylinder misfires, you name it. It's barely driveable. I wonder what I could have done wrong? I replaced the inlet manifold gaskets, check all the vacuum hoses as best I can and cleaned the throttle body. Since the rough idle problem, even though I had no problems whatsoever before changing the starter, at 100,000 miles, I've also changed the vanos solenoids, coils and plugs but still no improvement in the rough idle. I've also noticed a strong unburned petrol smell in the cabin? I'm at a loss as to what to try now. Any help appreciated.[IMG][/IMG]

[Opie55]

Just so you know, this is a forum for the 2012 and newer 6 series. There is not one here for your car. Having said that, if it ran well before then you obviously missed something putting it back together. The two most likely causes are you did not fully seat some electrical connector or you have a vacuum leak. I would get a vacuum gauge, find out what vacuum it should pull at idle and check to see what vacuum it has. Also, if that is your house, can I come visit?

[Sixy]

Originally Posted by Opie55

Just so you know, this is a forum for the 2012 and newer 6 series. There is not one here for your car. Having said that, if it ran well before then you obviously missed something putting it back together. The two most likely causes are you did not fully seat some electrical connector or you have a vacuum leak. I would get a vacuum gauge, find out what vacuum it should pull at idle and check to see what vacuum it has. Also, if that is your house, can I come visit?

No forum for my old car. Bugger! I guess it's a bit past it, like me. Yes, I'll have to 'rip' it all out and check again. The vacuum seems good, I checked. These N52 models are great, but like all BMW's, once the warranty runs out, beware! Mind you, mine ran out eons ago! Lol.

[Opie55]

Originally Posted by Sixy

No forum for my old car. Bugger! I guess it's a bit past it, like me. Yes, I'll have to 'rip' it all out and check again. The vacuum seems good, I checked. These N52 models are great, but like all BMW's, once the warranty runs out, beware! Mind you, mine ran out eons ago! Lol.

I've done that exact job on an N54 5-Series. Same basic engine. Lots of things to remember to put back correctly. And it seems easy to unseat one of the rubber manifold seals. But if your vacuum is good, then that seems unlikely. I have no warranty on my 2015 either. There are forums for your car, just not on Bimmerpost. But given how common that engine is, general internet searches or an inquiry in a 5-series forum might be better because they are more common and have more DIY types. Forgetting whatever it was you forgot might be common.