4.8is engine sludge, rough idle etc

[four.8is]

As the title says, as soon as cold weather hit the northwest , Ive started experiencing a rough idle that was not present until now.
I’ve had the car die at a light this past summer in 114 degrees , hooked up the computer and it was a bad MAF. Worked well after I changed that.
Also changed the CCV membranes, they were good no cracks etc, changed them 50k miles ago but did notice this sludge in the engine, is this normal? (See picture)

I’ve ran 3 or 4 injector cleaner bottles for the past couple months, and that was the only thing I did out of the ordinary.
No codes, no lights etc.
how can I get to the bottom of this?
I have DIS/INPA . Any tests I can do there?
Car has 154k miles

I do have a coolant leak that has developed in the last 3-4 days , very slow leak but planning to take the shield off and trace it .

What would you guys do?

[upallnight]

Originally Posted by four.8is

As the title says, as soon as cold weather hit the northwest , Ive started experiencing a rough idle that was not present until now.
I’ve had the car die at a light this past summer in 114 degrees , hooked up the computer and it was a bad MAF. Worked well after I changed that.
Also changed the CCV membranes, they were good no cracks etc, changed them 50k miles ago but did notice this sludge in the engine, is this normal? (See picture)

I’ve ran 3 or 4 injector cleaner bottles for the past couple months, and that was the only thing I did out of the ordinary.
No codes, no lights etc.
how can I get to the bottom of this?
I have DIS/INPA . Any tests I can do there?
Car has 154k miles

I do have a coolant leak that has developed in the last 3-4 days , very slow leak but planning to take the shield off and trace it .

What would you guys do?

That would be normal if the original BMW owner used BMW maintenance program for the oil change. BMW originally just provided a 15,000 miles oil change as part of their "FREE" maintenance program, but after owners started experiencing sludge build up in their BMW, that interval was revised to 7500 miles. The oil service light was reprogram for the revised oil service mileage. Dealers would not provide the free oil maintenance service if the oil service light did not call for a service.

I would change the oil every 5,000 miles.

[four.8is]

This was a 1 owner car maintained exclusively at the dealer til 92k miles so what you say makes sense, but I don’t remember that sludge being there last time I changed the CCV. I change the oil twice a year, somewhere between 6k-8k...don’t think that’s a problem.

[electricalserv x5]

What You think is a rough idle could be bad motor mounts.............it is shaking at cold start.I had the same on my 4.8is . changed out the engine mounts and it was gone.

[four.8is]

Originally Posted by electricalserv x5

What You think is a rough idle could be bad motor mounts.............it is shaking at cold start.I had the same on my 4.8is . changed out the engine mounts and it was gone.

Interesting. I’ll look into that. They’ve never been changed.
Thanks!

[SigBoi]

Originally Posted by electricalserv x5

What You think is a rough idle could be bad motor mounts.............it is shaking at cold start.I had the same on my 4.8is . changed out the engine mounts and it was gone.

Was it a lot of work to change out the motor mounts? I'm having similar symptoms as well.