kskane

I pulled out my spark plugs after 30K's, does it really looks this bad after only 30K KM's?

KyleB

They're not terrible, look a wee bit oil fouled to me. Have you ever replaced your CCV valve and pipes? Do all of the plugs look like that? If your valve cover gasket was worn oil can seep down around and through the spark plug grommets and foul out the plugs. If your car seems to be running strong and youre not getting misfiring or abnormal oil consumption i wouldnt worry about it. how many miles on the car?

kskane

Mileage on car 233K KM's. All look the same, and I pulled them cause I was doing my VCG. Car runs smooth, but have had random 3-4 times shaky experience at the red light. I have changed the plugs anyway and kept these for backup. Should I check something else?

Kaane

I would do a leakdown or compression test. You are fouling the plugs with oil. So you either have blow by through the rings or valves.

kskane

Valve cover was leaking for sure and the car was either leaking or drinking 1L oil a week. If the VCG is fixed what do you mean by the rings?

KyleB

He means the rings on the pistons (oil scraper and two compression rings). Unless you have a ton of mileage I doubt its that, and by a ton I mean 300K+. BMW bottom ends are incredibly stout, always have been.

Keep tabs on your oil loss/consumption. There are other places M5X engines are known for leaking from.

Kaane

I'd still do a leakdown test. 1L of oil a week is a lot of oil. Could have worn valve guides or seals. Check your entire pcv system as well.

KyleB

yep, I'm thinking PCV system as well. Also check oil filter housing gasket, oil pan gasket. When the oil filter housing gasket goes oil loss goes through the roof. Agree 1L a week is a huge amount.

kskane

But will that impact on the spark plugs? Is there a DIY for this PCV?

KyleB

yea, google "M54 CCV" and you'll find tons of info on it. get your parts from pelican, it's a fairly cheap fix and common failure point on M5X engines. check your oil filter housing gasket too. that gasket fails a lot, pukes oil, and costs about $5.