Good Morning everyone, I hope you are all well. This is for my 07 530xi e60 with n52 engine. I'm trying to find the cause of my poor idle. My idle, especially at cold appears to be low, and feels like it is misfiring. No cel, and no codes.
I have done spark plugs last year with oe plugs and replaced all of the coils two weeks ago with new Delphi units. The coils haven't made a difference. I don't know where I need to start looking, or if I need to say screw it and get it to my shop before it does something stupid.

Thanks in advance.
Michael

 

The next thing I would do is a smoke test to see if I have a vacuum leak. That is probably were your problem lies if you have not changed any hoses out before.

 

Sean,

I don't know how many miles are on the OP's car.

In the event his CCV orange rubber diaphragm embedded in the rear of the plastic valve cover was torn or malfunctioning causing vacuum issues...

When he does a smoke test how will he know if the diaphragm in the valve cover is torn?

 

That's exactly how I found out my CCV was bad. But mine was really bad at 10 years. I went ahead and replaced all hoses also because they were real brittle.

 

I don't like removing parts until I do a smoke test since it's easy to do.

 

The miles are around 215k I would think that a vacuum leak would cause codes and a high idle, but that may just be me being used to older systems.

 

You are right it should but weird things happen with these cars. I had a vacuum leak and bad coil for a while and never got a code. I would get a rough idle when cold and that's it. Then I didn't have the time to troubleshoot but did notice when I hooked up INPA it did trigger a message still no CEL. When I had time about a year later I decided to do some troubleshooting and my CCV and a hose that was bad along with a coil on the frenzy. Changed everything out with the VC gasket and haven't had an issue since.

If you have INPA see if it through a message.

 

Unfortunately my laptops are packed away, as I am fortunately buying a house and moving away from this development where I cannot work on my vehicles. I also never really had the opportunity to get familiar with INPA, but hopefully that will change when I can freely work on my car without worrying about getting fined/evicted. My worries were something on the precipice of failure like a fuel pump or something that could cause it to just not run. I do realize that this is immensely unhelpful. Ccv would be crank case ventilation I presume?

 

Yes you are correct. I looked up information for your application. You may want to check hoses also to be sure they are good. I'm not saying this is your issue but it very well could be. This is why a suggested a smoke test. Scott was correct with you CCV. Mine is different in a M54 engine which cracked on the CCV itself.

CCV for your car

Instructions

 

I had a vacuum leak (hose) and my car threw no codes at all. Just had crappy idle more so when cold.