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E63 owner here but there is much better info / knowledge of the M156 in this forum so I hope you don't mind me posting. I just sent my E63 to my brother (who lives in Las Vegas) and he noted this "knocking" noise when revving it up a bit. It's not the injector tick at idle, it's a loud knock you can hear clearly at the 9-second mark of this video. Please let me know what you guys think is going on. The car has been on LM 5w40 for 6k miles and I had not heard this noise before. No codes or other symptoms.
12 C63BS Magno Alanite Grey, 25 X5 Msport, 08 BMW E93, Ducati Hyper 698
Sounds like lifter tick to me - is this the first time it has happened or does it happen all the time - mine used to do it if the car sat for more than 3 or 4 days at a time would get some tick someones last like my entire drive to work (15-20 minutes) shut it off and start it later and would be gone and would generally not happen if I drove the car daily. It was just a lifter or 2 bleeding down and ticking, no wear or issues just lack of oil in the lifter from sitting and takes a bit to get oil back in it.
If it is just doing it constantly and wasn't sitting I would pull the valve cover and have a look, only takes a couple hours to see what is going and feel better about it.
Last edited by roadkillrob; Nov 16, 2021 at 09:16 PM.
sounds like lifter but...i've had 2 sets of lifters replaced and the noise returns at random times. my adjusters have never been replaced and i do get a code from time to time so i'll have to change my cam adjusters at some point. mobil 1 is not the best you could put into your car. LiquiMoly or Motul should help with noise, but not eliminate. even today...at times the knocking appears and goes away after 3-5 minutes of driving.
A depressurized valve bucket is loud at idle and it's more of a hollow tick sound.
That also sounds like an up to temp engine (could be wrong) so the bucket should have pressurized by then. That and the fact it's not as obvious at idle it doesn't sound like a bucket that needs to fill with oil.
12 C63BS Magno Alanite Grey, 25 X5 Msport, 08 BMW E93, Ducati Hyper 698
It is pretty hard to tell on these phone videos to accurately here and identify the sound.
I might suggest a mechanics stethoscope or even just your ear to to identify the location of the noise as that will help tell what it is also.
Cam Adjusters typically rattle on a cold start until they get oil pressure and then quiet, once they wear enough they just rattle always - noise at the very front of the head.
Buckets from bleed down - typically make noise after it sits on a cold start, more likely the longer it sits, will go away once oil pressurizes the bucket and fills it, I have had this take sometimes 15-20 minutes of driving, seems to somehow be better if you run for a few minutes and shut off and start again - tends to get quieter with revs also.
CA's you really can't tell visually without taking them off and taking them apart, if the noise is further back on the head, then pulling the cover to inspect is worth doing.
Worn out bucket/cam - will just make the noise all the time warm or cold and not usually go away with revs although may get quieter with revs.
Thanks for the input guys (I’m the brother that has the car now). The noise seems to be worse when the engine is up to temp. It seems to be fairly constant once the engine is warm (ie it’s not a cold start noise). Will take it to a shop for assessment but wanted to get an idea what others thought first since I don’t know any of the shops here. I did take it to a shop but they declined to work on the car and didn’t even really examine it. If anyone has recommendations I’m all ears.
12 C63BS Magno Alanite Grey, 25 X5 Msport, 08 BMW E93, Ducati Hyper 698
Cams are worn but what I would expect for the miles and not the cause of any noise with minimal wear, but they will continue to wear and may cause issues if they do in the future, just something to keep an eye on, as they wear they become rough and will start to dig groves into the lifters.
If you do the lifters, make sure they use the updated SLS part number, it is what the old part numbers supersede to for all M156 engines and have a coated top which helps with the wear and they have improved oil valves to keep the oil in the lifter.
Just to close the loop I went ahead and had the lifters done as well as the head bolts. 4 of the lifters had gone soft. The noise is completely gone. Car runs well. They said the cams looked fine and left them as-is. Thanks to everyone for their input. I will add some pics of the head bolts. I’m no expert so I can’t comment on the head bolts but I am quite happy to have a car that doesn’t tick or knock. Will take it easy for a thousand miles or so and will then exercise the M156.
A loose fitting cam adjuster pin will sometimes make that noise as it rattles back and forth at low oil pressure until the higher oil pressure unlocks it. I don’t have details on when the pin unlocks unfortunately so I can’t nail it 100%. If a pin rattles that much with increasing revs the plate’s likely worn and vibrating on the worn areas of the plate.
My guess with the adjuster is that it’s infinitely variable and the pin unlocks from engine start allows for good fuel economy when keeping below 3500 rpms and good power above 3500 rpms.
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