IIRC the scuttlebutt is that there's not much you can do about the oil consumption on the M54 because it's a manufacturing issue and or related to the PCV tube which drains into the dipstick tube.
Engine Cleaner/Flush for 2002 BMW 325it with 270k miles?
- Thread starter mckenzie333
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Yup, couldn't remember if it was 2001 or 2003.
As I've noted, the 3L version of the M54 (M54B30) was built with low tension oil control rings. Yes, the PVC is crap-it was designed by an engineer who'd been fired by Audi!
Sorry I didn't see that post of yours. As an aside back then I read a rumor that the consumption could've been rectified if a torque plate had been used during the honing (cylinders) process but that it would've been prohibitively expensive. My M54 (ZHP) wasn't too bad but it was a 6-spd.
Have you checked out E46Fanatics. Great website with lots of tips and tricks. Search for "02pilot mod." It increases vacuum at the pvc. Also, read up on DSMO. This stuff really cleans when its heated up. There's a long description of how to use this stuff on the site, also.
https://www.e46fanatics.com/threads/ultimate-engine-flush-process-part-1.1285390/
https://www.e46fanatics.com/threads...the-engine-part-2-combustion-chamber.1285432/
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Yes, back in the early 2000's.
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Thanks, Marconi.I had read there was a way to restructure the pcv valve tubing so less oil would be lost. Is this similar to the ow pilot mod you reference? I will definitely search e46 fanatics.
02pilot mod: The factory pvc has 4 ports, but the M54 engine uses only 3 ports. See item #6 in link #1 below. The unused port is connected via a vacuum hose to a port on the back of the cylinder head. See item #22 in link #2 below. This increases the vacuum in the pvc valve, reducing oil consumption. But, I think it's a band-aide. It doesn't fix the problem: low tension oil rings and smallish oil drain back holes in the pistons. These get clogged with carbonized oil. The easiest way to clean these is to follow the DMSO process. JMHO YMMV
1. https://www.realoem.com/bmw/enUS/showparts?id=BN53-USA-01-2002-E46-BMW-330Ci&diagId=11_2194
2. https://www.realoem.com/bmw/enUS/showparts?id=BN53-USA-01-2002-E46-BMW-330Ci&diagId=11_2213
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Thanks so much for this Input. I had read about this a year ago but your help really helps..I’ll share with my mechanic. Do you think the mod will help to some extent ?
You're welcome.
