Gunked up spark plug

Curry Addict

my car started misfiring today. I found My cylinder 2 spark plug had gunked up with black sludge. cleaned it up, refitted, cleared the code and shes running grand again. I changed this plug about 6mths ago for the same issue.
any ideas as to whats causing this?

icjzfmq7ewon1t

It could be a valve seal maybe

haulagebasher

Yup. Bad valve stem seals or else stuck or broken piston rings is really the only thing that could cause fouling on a single cylinder. In either case, It's a case a fair amount of strip down is required. If it's been missing for a while, you cat is probably screwed also.

Nissan doctor

Was it just like sooty black or wet oily black?

What car is it?

Curry Addict

it was wet oily black this time but last time it was sooty/charred black so i replaced it. it was in just a year when i replaced it.

Nissan doctor

Curry Addict wrote: »

it was wet oily black this time but last time it was sooty/charred black so i replaced it. it was in just a year when i replaced it.

When you start the car from cold, is there any smoke visible?

Curry Addict

a small amount amount of colourless smoke on cold start.
she is greedy for oil tho E39 m54 engine.

Nissan doctor

Curry Addict wrote: »

a small amount amount of colourless smoke on cold start.
she is greedy for oil tho E39 m54 engine.

Well if your burning oil(assuming there is no external leak to explain the oil loss) then further diagnosis you be needed to see where the issue lies.

If the engine is running perfectly and smoothly etc with no power issues then its likely a valve stem oil seal issue. If its been an ongoing problem you could have further issues with lambda sensors/cat etc.

Curry Addict

no leaks as ive investigated and replaced everything there. she purrs along driving beautifully.
they say the oil burning is more likely the piston rings as the valve seals rarely fail on these engines. im looking into DIYing the piston rings atm as im very competent and that would be a nice challenge, im finding it difficult to find a good guide for that.
i was hoping that the spark plug gunking was not related but maybe my problem is progressing. its guzzling a litre every 250miles for a year now.

Nissan doctor

Curry Addict wrote: »

no leaks as ive investigated and replaced everything there. she purrs along driving beautifully.
they say the oil burning is more likely the piston rings as the valve seals rarely fail on these engines. im looking into DIYing the piston rings atm as im very competent and that would be a nice challenge, im finding it difficult to find a good guide for that.
i was hoping that the spark plug gunking was not related but maybe my problem is progressing. its guzzling a litre every 250miles for a year now.

TBH if it was rings causing it to use that much oil then you would have other issues such as sluggish starting and lack of power at higher RPM.

Curry Addict

ok well i tell you where im at then

ive replaced the ccv and related hoses. consumption of oil escalated from 1ltr per 700 miles to 1ltr per 400miles after this, it may or may not be related.
checked the dip stick hose and all other oil related hoses.
replaced the valve cover gasket.
replaced the oil filter housing gasket.
replaced the vanos o rings.
checked the oil sump seal.

this doesnt leave a lot left hence suspecting the piston rings.
any insight appreciated!

macc7

Curry Addict wrote: »

ok well i tell you where im at then

ive replaced the ccv and related hoses. consumption of oil escalated from 1ltr per 700 miles to 1ltr per 400miles after this, it may or may not be related.
checked the dip stick hose and all other oil related hoses.
replaced the valve cover gasket.
replaced the oil filter housing gasket.
replaced the vanos o rings.
checked the oil sump seal.

this doesnt leave a lot left hence suspecting the piston rings.
any insight appreciated!

Hi
Bought one of these 6 months ago ,60,000 with full service history .soon after oil light came on burning 1 liter every 1500 miles .in my opinion oil burning is a result of sludge buildup from short trips and extended oil servicing .
Since buying the car I have performed the following which has resulted in little or no oil consumption in the past 600 miles
Oil filter housing gasket
Vanos seal replacement
Oil dipstick cleaning
Ccv valve was changed by previous owner
Disa valve inspection ok
Throttle body ok
Intake ducts ok
Icv ok
have you done ccv test ,warm engine running remove oil cap drop in revs and small vacuum on dipstick tube
You should check all your ccv pipe connections again ,especially your dipstick tube when I installed mine first time I noticed oil level was reading very low and the bolt did not line up the same as before it took a lot of effort to seat it correctly in the sump with the o ring .There are also plenty of posts on all BMW forums on engine washes ect
when you did your Vanos was it covered in sludge ,pistons ect what. .condition was your rocker cover .mine was covered in the stuff ,I plan to do frequent oil and filter changes every 7000 miles to try and clean it up .I pulled out a spark plug and could see sludge / soot in the engine under it other than that very happy with the car

Curry Addict

mine started using oil at around 65,000 miles. it staretd with a litre every 1,500miles and deteriorated in steps to a litre every 250miles now at 97,000miles. I have read everything out there on this problem and checked everything bar the engine internals...

the vanos was in good shape and the dip stick tube is properly seated. she runs better than ever after all the work i did. once i top her up shes happy to go
i would like to fix this problem as the drive is still so sweet and doesnt seem to suffer from age like any other car ive ever had.

macc7

Hi that's some amount of oil to be going through ,the only positive is I would say it takes your mind off petrol consumption .before you go an rip engine apart have you looked at posts in relation to catch cans and using the unused port on the ccv valve to fix oil usage ,seems to work . Might be a quick cheap fix .I am no expert but if engine is running as good as you say (apart from oil usage issues ) I would find it hard to believe that the engine needs to be ripped to fix the problem ,have you seen the u tube of the hydrolocked X5 would this be something along the lines of your issue they said it was due to a failed ccv valve .hope u get it sorted

anonyl

have you done a compression test?

Curry Addict

macc7 wrote: »

Hi that's some amount of oil to be going through ,the only positive is I would say it takes your mind off petrol consumption .before you go an rip engine apart have you looked at posts in relation to catch cans and using the unused port on the ccv valve to fix oil usage ,seems to work . Might be a quick cheap fix .I am no expert but if engine is running as good as you say (apart from oil usage issues ) I would find it hard to believe that the engine needs to be ripped to fix the problem ,have you seen the u tube of the hydrolocked X5 would this be something along the lines of your issue they said it was due to a failed ccv valve .hope u get it sorted

i read about using the unused port on the ccv but didnt do it, as i wanted a real solution.
it is baffling as to what is going on with my oil. the hydro-locked x5 does seem to share characteristics of my problem but i have replaced the ccv.

Curry Addict

anonyl wrote: »

have you done a compression test?

i just looked into doing this. kits are cheap enough so i guess that would be a good next step.

anonyl

Curry Addict wrote: »

i just looked into doing this. kits are cheap enough so i guess that would be a good next step.

:)