do these plugs look healthy? - The Unofficial BMW M5 Messageboard (m5board.com)

Avusblue · 5th January 2007, 03:00

Out of an '00 M5 with 60kmiles I pulled these plugs. There were no issues nor codes present, I just thought that it was time to change. The driver side was covered with oil while the pass. side was dry as a bone. Please share your opinions on them. thanks

phid_bombadier · 5th January 2007, 03:29

Your passenger labeled ones look more "oily" than the drivers side labeled ones. (Oil on the threads of the plugs.)

In general it looks like the car is running rich with all the carbon deposits on the plugs. I think proper running plugs should be brownish without much build up. Too much white/ash and you're running lean.

Oil on the threads could mean valve cover gaskets are leaking a bit. Had that symptom on my E36M3 and replacing the gaskets cleaned up the threads.

Do you do a lot of local driving? Oil consumption? Trying to think if that's causing the soot build up on the tips.

Comments from my experience, others may have better technical knowledge/info.

HTH,
--Mike

Jefsmr2 · 5th January 2007, 03:59

I agree with Mike. Both sides actually look oily and your car looks like it's running rich to me as well with all the deposits.
As far as your oily plugs, with the best of my knowledge, it can be a couple of things.
#1. Leaky valve cover gasket.
#2. Oil pumping past worn piston rings.

To make sure it's not the rings you can always do a compression test. If compression is fine it most likely the gasket. If you have bad compression it's most likely the rings or both.

Just my .02

Germanwrecker · 5th January 2007, 04:37

Hey, since owning my M5 I have found myself working on quite a few and have seen this a few times, all the other opinions are correct and I would say that these are the common causes but if your gasket isn't leaking someone has spilled oil in the valley for the plugs and it has sat there causing all the oil on your threads. I have seen this twice here and I would say it is the dealer apprentice doing services in a rush!!! If this is the case clean it out as my friends 540 caught fire from it!

jclyman · 5th January 2007, 06:58

If it were my car, I would do three things.

1.) Do a compression test ... Passenger side # 2 definitely looks like oil getting past the rings. (Can't comment on the oil on the threads ... my plugs always have some oil on the threads as I put a little bit of light grease on them when installing.)
2.) Watch your oil consumption closely for about 5,000 miles (actually, I watch it closely all the time).

You didn't say how hard you drove the car ... It looks like it hasn't been driven hard ... more like just around town ...
3.) I would drive it like it was stolen ... It doesn't look too rich to me ... if driven properly, it will be fine, given that excess oil isn't getting past the rings ...

Replace them.

mottati · 5th January 2007, 07:12

i don't think they look too bad, insulator is relatively clean. Some debris on the ground electrode. I'd certainly look for a valve cover oil leak, with those oily threads. I'd drive it hard for a few days, maybe throw some techron in a couple of tanks, and if you're concerned, check them again in a month or so. I posted pics of my plugs with about 57k on them a couple years back, if you want to search for a comparison.
mike

Avusblue · 5th January 2007, 07:33

Thanks everyone for your inputs. I had just purchased the car-put about 1500 miles on it. I will monitor the oil consumption as sugested. Also, I noticed dust particles, almost fine powder, on the bumper. I have to admit, I haven't driven it hard at all for those 1500 miles. Its time to let out the beast.

jclyman · 5th January 2007, 07:48

Quote:

Originally Posted by Avusblue

Thanks everyone for your inputs. I had just purchased the car-put about 1500 miles on it. I will monitor the oil consumption as sugested. Also, I noticed dust particles, almost fine powder, on the bumper. I have to admit, I haven't driven it hard at all for those 1500 miles. Its time to let out the beast.

Remember, BMWs are "The Ultimate Driving Machine." DRIVE IT, you won't hurt it. The car will love you for it ... no kidding.

Up · 5th January 2007, 13:42

hey guys - innocent question here: Can leaky oil gaskets rob our engines of power? My Spidey sense tells me yes, wanted your input.

Up.

jclyman · 5th January 2007, 17:16

Quote:

Originally Posted by Up

hey guys - innocent question here: Can leaky oil gaskets rob our engines of power? My Spidey sense tells me yes, wanted your input.

Up.

May be something new that I am not aware of, but ... I don't think so ... other than the added weight of the oil on the outside of the engine ...