N54 335i Leaky/cracked valve cover? Help!
N54 335i Leaky/cracked valve cover? Help!
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Discussion

Silverbullet767

Original Poster:

11,360 posts

237 months

Friday 9th February 2018
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Having a bit of trouble with my car, symptoms include.

Occasional puffs of white smoke under hard acceleration, very occasional spluttering under hard acceleration. Steam coming from left hand kidney grill after a drive in cold conditions, very thin milky residue on underside of oil cap, and I think there's oil getting to the spark plugs. I'll pull a couple to be sure and have a look.

Does this sound more like a valve cover seal or a dreaded headgasket?

helix402

7,913 posts

213 months

Friday 9th February 2018
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It sounds like neither. More likely faulty coil/injector or high pressure pump.

Silverbullet767

Original Poster:

11,360 posts

237 months

Sunday 11th February 2018
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How would I diagnose that?

helix402

7,913 posts

213 months

Sunday 11th February 2018
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Start by reading the DME fault memory.

Silverbullet767

Original Poster:

11,360 posts

237 months

Monday 12th February 2018
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Well, now I'm really confused. No fault codes whatsoever. Fault codes read by Carly for BMW.

Dannbodge

2,390 posts

152 months

Tuesday 13th February 2018
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Silverbullet767 said:
Having a bit of trouble with my car, symptoms include.

Occasional puffs of white smoke under hard acceleration, very occasional spluttering under hard acceleration. Steam coming from left hand kidney grill after a drive in cold conditions, very thin milky residue on underside of oil cap, and I think there's oil getting to the spark plugs. I'll pull a couple to be sure and have a look.

Does this sound more like a valve cover seal or a dreaded headgasket?
Puffs of white smoke under hard accel - It's cold out atm. Probably just steam?
Spluttering on hard accel - Has it been walnut blasted, when were the plugs changed?
Steam from kidney grill - No idea.
Residue on oil cap - Do you do short journeys?

Cracked valve covers and pretty common.
Don't waste your time with just a gasket, once it's had a gasket the cover splits and causes more issues. If it needs a gasket, just get the cover.

Headgasket is unlikely.

My N54 had a valve cover gasket (by BMW) and about 6 months later, the valve cover had split which contaminated a couple of injectors.

SebringMan

1,774 posts

217 months

Tuesday 13th February 2018
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Do the covers crack due to being overtorqued? I know on my M3 the valve cover bolts only need to be tightened up to 10Nm. That's barely hand tight when checked against my wrench. 11,000 miles later I have no leaks. Many valve covers don't need to be tightened alot.

NeilMick

153 posts

160 months

Tuesday 13th February 2018
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When my valve cover went it took a coil with it and developed a misfire!

Silverbullet767

Original Poster:

11,360 posts

237 months

Tuesday 13th February 2018
quotequote all
Dannbodge said:
Puffs of white smoke under hard accel - It's cold out atm. Probably just steam?
Spluttering on hard accel - Has it been walnut blasted, when were the plugs changed?
Steam from kidney grill - No idea.
Residue on oil cap - Do you do short journeys?

Cracked valve covers and pretty common.
Don't waste your time with just a gasket, once it's had a gasket the cover splits and causes more issues. If it needs a gasket, just get the cover.

Headgasket is unlikely.

My N54 had a valve cover gasket (by BMW) and about 6 months later, the valve cover had split which contaminated a couple of injectors.
It's a funny one, 95% throttle, no white smoke, only at 100% (I have a JB4)
Walnut blasted 20,000 miles ago. Plugs around 5000 miles after that.
I do short journeys, my work is only 15 min drive away, the oil gets up to temperature just as I arrive.

I might just change the valve cover, found a great DIY here.

http://bd8ba3c866c8cbc330ab-7b26c6f3e01bf511d4da33...

To double check the correct part, would I need 11127565284?



Silverbullet767

Original Poster:

11,360 posts

237 months

Thursday 21st June 2018
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To end the thread, valve cover changed over with new gaskets.

Problem solved.