plowery21

Anyone know what could cause a Cracked Valve Cover on a N64. Took my 535i for a check engine light and that is what they found. Car was throwing mixture control codes. After ok High and Low fuel pressure tests they removed the plastic covers and found the crack. Note says "Found Smoke coming from Engine Cover". Replaced under CPO for $50 deductible which was great, but Im more concerned about the cause and what damage (future issues) this may have caused.

Service guy says I got a mid-life oil change for free which is a bonus I guess.

Any insight is appreciated.

texasmr2

Wow that is very strange, I would be wondering if this is a common N64 issue or just a freak occurrence .

DavidF

Fluke. It would not have caused any collateral or long term damage. The crankcase is under vacuum during normal operation. The crack caused a vacuum leak and hence the check engine light. "smoke" must have just been oil vapor which is normal.

plowery21

Thanks David.

RIHI

The last guy must've over tightened the bolts. They normally do not crack. I've seen them warped but cracked is only when the bolts are over tightened or the cover is dropped.

plowery21

Thanks RIHI… that leads me to another question, why would the valve cover be removed previously. The BMW records show no major engine repair other than the HPFP. Is that normal maintenance?

Car runs great..just worried for the 100,001 mile non-warranty fix.