Gents,

About 3 weeks ago, I purchased a 2006 M5. I absolutely love the car. It has the SMG transmission which I thought I'd hate, but I really enjoy, especially during spirited driving. However, on my first road trip and after travelling at speeds well over 100 mph, the "service engine soon" light came on my dash, and on the screens, "increased emissions" warnings were popping up. Days later, the warnings remain.

Now, the car was idle at the dealership for around 70 days. I spoke to the dealership, and they said it could be too much air in my gas tank after I pumped gas or simply just driving for a few hours after sitting for so long at the dealer and being idle/cold.

To take it to the dealership would be a pain in the ass to have them shut the warning light off. I wanted, though, to get all of your opinions first, so I know exactly what I'm dealing with.

Thanks!

 

Not sure where you stand on your issue, as not many people respond to posts on here. I recently bought a 2006 M5, smg. My car did the same thing, but, in a few days, the light went out. Took it to a local independent BMW shop, analyzed it and they said there were 74 random misfires stored in the computer. It has done this twice now, but they say there is absolutely nothing wrong with my car at least. I don't know, the V10 is a different beast they say, to me anyway, thats not much of an answer. Funny you mention air in the gas tank. Sometimes when I put gas in, start the car and get to a red light, it will idle irratic as hell, then after a bit, stops it and behaves itself

 

sometimes misfires in conjunction with increased emissions (especially if misfires are all on the same bank) are indicative of a o2 sensor going out.

 

There are 2 ionic control boxes, one for each bank and if the misfires are on one side, swap the boxes and see if the misfires go to the other side. These boxes have been problematic on these cars. Easy to do yourself. They sit on the top front of each valve cover.

 

Did you have a complete diagnostic done on the vehicle prior to purchase? If not, you should. A computer readout on all your engine functions should tell you exactly where the problem is.

 

My misfires were all over the board, totally random and it did [does] it only at start up, the goes away. Do you, or someone have any idea why I will hear valve clatter between 2,500 and 3,000 RPM? Reminds me at times of the old distributor car, when the timing is too far advanced

 

I had that similar problem with a 2003 M3 once. It was an "emission warning" and my M3 lost power. The problem was the "catalytic". BMW has extended warranty regarding emissions; I think it is up to 75k miles no matter if original warranty expired. Hope this helps. They replaced my catalytic the same day it happened and viola!!