Buy BMW 330i Engine Valve Cover Gasket Sets

The engine valve cover gasket set (also called a rocker cover gasket, cam cover gasket, or valve cover seal) sits between the valve cover and the cylinder head. Its job is simple: keep engine oil inside while the top of the motor (cams/valvetrain) is working. Over time, heat and age harden the rubber. That's when leaks show up.

Ò330iÓ has been used on different 3-Series generations, so the engine - and the exact gasket set - depends on model year:

• E46 330i (approx. 2000-2006) uses the M54 inline-6. (Wikipedia)
• E90 330i (mid-2000s) uses the N52 inline-6 in many markets. (Wikipedia)
• F30 330i (2016-2019) moved to the B48 2.0-liter turbo four. (Wikipedia)
• G20 330i (2019-present) continues with the B48 family. (Wikipedia)

To confirm what fits your exact car, look up your VIN in the official BMW parts diagrams at RealOEM.

• Burning-oil smell after drives, sometimes a little smoke from the engine bay as oil hits the hot exhaust.
• Wet, oily edge around the valve cover.
• Oil in the spark-plug wells (misfires, rough idle).
• Slow oil loss between changes.
  Excess crankcase pressure (from a crankcase ventilation/PCV issue) can push oil past gaskets and seals, making leaks worse. (Wikipedia)

Gaskets age and flatten from heat cycles. On many modern BMWs (including B48 and N52 families), the cover is plastic and includes the crankcase ventilation pieces; plastic covers can warp or crack with age, which lets oil seep out even with a new gasket. (Driven SD)

BMW integrates crankcase ventilation into the cover on many newer engines. If the PCV function is out of spec, the engine may pull too much or too little vacuum in the crankcase, which can drive leaks. BMW service info publishes test ranges (for example, B48/B46 engines) and provides a procedure to measure crankcase vacuum during diagnosis. See BMW's Service Information bulletin excerpted via NHTSA and the BMW technical portal: PCV test PDF and BMW AOS. (static.nhtsa.gov, aos.bmwgroup.com)

Not every 330i uses the same gasket design. Verify your engine code and production date, then match the set (outer perimeter seal, spark-plug tube seals, and bolt grommets common on many sets) using BMW's official diagrams: RealOEM VIN lookup.

Small seep = usually safe for short trips if you keep oil topped up. But oil can drip onto the exhaust and smoke, and a fast leak risks low oil level and misfires from oil in plug wells. Fix sooner rather than later, and check for any open safety recalls by VIN on the NHTSA recall site.

When servicing a BMW valve/rocker/cam cover gasket, many owners also inspect:

• PCV/vent lines and the cover's built-in PCV passages (where applicable). (Driven SD)
• Spark plugs and coils if oil reached the tubes.
• On N52 engines, the valvetronic motor gasket and eccentric-shaft sensor area - common oil spots near the cover. (Multiple BMW owner-tech communities document these as recurring leak points.) (e90post.com, zpost.com)

1. Start cold. Remove engine covers and hoses as needed.
2. Detach ignition coils and harness from the cover.
3. Lift the valve cover, keeping debris out.
4. Clean both mating surfaces until dry and oil-free.
5. Seat the new gasket(s) in the cover.
6. Use only small dabs of sealant at specific corners/joints if your engine design calls for it (see next section).
7. Re-install the cover and tighten fasteners in stages, center-out, to the factory spec.
8. Re-fit coils/hoses and clear any oil residue so you can spot new leaks.
   Improper sealant use or uneven tightening are two of the top reasons fresh gaskets leak. (Fel-Pro)

BMW service literature calls for clean, dry rubber gaskets and light sealant only at certain ÒjointÓ spots (for example, timing-cover corners or half-moon areas on some engines). Do not smear RTV around the whole perimeter - that can make leaks worse. Always follow the tightening sequence and torque in the BMW service manual (available via BMW AOS). For general gasket best practices, Fel-Pro's tech note explains when a tiny dab of RTV is appropriate. (, Fel-Pro)

A little smoke or smell can linger for a short time as leftover oil burns off the exhaust. Wipe everything clean and re-check in a day or two. If you still see fresh oil, re-inspect the cover for warping/cracks and make sure each spark-plug tube seal is seated. (A warped plastic cover will often keep leaking.) (Bimmerpost)

Catch and recycle used engine oil and the old filter properly. The U.S. EPA explains how and where to recycle, and the federal rules define DIY oil collection centers. See EPA used-oil guide and 40 CFR Part 279. (US EPA, ecfr.gov)

• Engines used across 330i generations: M54, N52, B48. (Wikipedia)
• Chassis overviews: E46, E90, F30, G20. (Wikipedia)
• Parts diagrams & VIN lookup: RealOEM.
• BMW official service portal: AOS (Aftersales Online System).
• PCV & crankcase vacuum test bulletin (for turbo-modular engines incl. B48/B46): NHTSA-hosted PDF.

Q: What does a valve cover gasket set include?
A: On many BMW engines it includes the main perimeter gasket, spark-plug tube seals, and new rubber grommets for the cover bolts. Always confirm kit contents and part numbers for your VIN using BMW diagrams.

Q: How do I know which gasket set my 330i needs?
A: Identify your engine (M54, N52, or B48 for most 330i years), then match the part via VIN on . Cross-check engine families here: E46/M54, E90/N52, F30 & G20/B48. (realoem.com, Wikipedia)

Q: Why do BMW valve/rocker cover gaskets leak so often?
A: Heat cycles and age flatten rubber. If crankcase ventilation is not working right, pressure builds and pushes oil out. Many newer BMWs integrate PCV in the cover, so a worn cover can also leak. (Wikipedia, Driven SD)

Q: Is a burning-oil smell normal with this leak?
A: Yes. Oil can drip onto the hot exhaust and make smoke or a strong smell until repaired. Fix leaks early to avoid mess and misfires.

Q: My spark-plug wells are oily. Is that the valve cover gasket?
A: Usually, yes. The tube seals inside the gasket set keep oil out of the plug wells; when they harden, oil gathers around the plugs and coils and can cause misfires.

Q: Do I need sealant?
A: Use a small dab only where BMW specifies (corners/joints). Don't smear RTV around the entire gasket - that can cause leaks. Review BMW's service info and Fel-Pro's general sealant guidance. (aos.bmwgroup.com, Fel-Pro)

Q: How tight should the bolts be?
A: Follow the BMW torque spec for your exact engine and the proper center-out tightening pattern. Overtightening can warp or crack plastic covers. Check specs in BMW AOS.

Q: Can a cracked or warped cover keep leaking even after a new gasket?
A: Yes. If the cover is distorted, the new gasket may not seal. Inspect the cover closely; many owners of N-series/B-series engines report replacing the whole cover when it's damaged. (Bimmerpost)

Q: What else should I consider replacing while I'm in there?
A: Ignition coil boots (if oil-soaked), spark plugs, oil filler cap seal, and - on N52 - the valvetronic motor gasket if you see oil in that area. Community tech threads document these as common leak points. (e90post.com, zpost.com)

Q: Will this fix show up in the car's service history?
A: If your shop uses BMW's service systems, they can update digital records. Info about the platform is at BMW AOS.

Q: How long should a new gasket last?
A: With a healthy PCV system and proper torque, many last years. Heat, short trips, and high crankcase pressure shorten life.

Q: Is there a set maintenance interval?
A: No set mileage. Replace when leaking or when the cover is removed for other work.

Q: Is it safe to DIY?
A: If you're comfortable with basic tools and follow the service manual, yes. Take your time, keep surfaces clean, and stick to the torque spec.

Q: What if the leak returns soon after the job?
A: Re-check torque after a heat cycle, inspect the corners where sealant is required, and verify the cover isn't cracked/warped. Also test crankcase vacuum to rule out a PCV issue (BMW provides specs and a test method). (static.nhtsa.gov)

Q: How do I dispose of the old oil and filter?
A: Bring used oil and filters to a recycling center. The EPA explains what to do and who accepts DIY oil. See the EPA guide and federal rules in 40 CFR Part 279. (US EPA, ecfr.gov)

Q: Where can I learn more about my specific 330i?
A: Use BMW's official info portal for service procedures (AOS) and BMW's parts diagrams for VIN-matched components (RealOEM). (aos.bmwgroup.com, realoem.com)

For exact procedures (tightening sequence, torque values, and sealant points), always follow BMW's official service information. (aos.bmwgroup.com)