Knocking Noise

[Graves]

So, I've been doing days of research on the forums and found multiple threads, however, most date back to 2019. Realizing it could be a plethora of things, any sort of solid answer? I read lifter tick, wastegate rattle, injectors, etc. it's not injectors, not convinced it could be the wastegate. I just changed the oil 3 days ago (5w30 BMW Twin Power), checked the catch can, oil filter and fished around inside the oil, no metal shavings, etc. just trying to be realist before I have someone tear into the motor. 2018 w/22k miles, BM3 stage 2, CH done, CBC done. No fault codes. I should note the car sits for a month or so at a time. Might just need to drive it more to keep some oil up top.

Video: https://youtube.com/shorts/HDh3ascXFvA?feature=share

[TopJimmy]

Vacuum pump or maybe a HPFP getting noisy? You can take a length of fish tank air line, stick one end near your ear, and use the other end to hunt for the noise source. HPFPs are on the right side below the plastic intake manifold, and the HPFPs sit on top of the vac pump.

[Graves]

Originally Posted by TopJimmy

Vacuum pump or maybe a HPFP getting noisy? You can take a length of fish tank air line, stick one end near your ear, and use the other end to hunt for the noise source. HPFPs are on the right side below the plastic intake manifold, and the HPFPs sit on top of the vac pump.

The noise definitely comes from the passenger side near the top. You can hear it good just kneeling next to the tire. I'm gonna try a different oil and drive it to see if the noise goes away. My dumbass drove it Saturday knowing the noise was there but didn't listen after it was good and warm if it was still present.

[flo93100]

Hello
It’s the exhaust camshaft torque issue
Mine do this sometimes

[TopJimmy]

Originally Posted by flo93100

Hello
It's the exhaust camshaft torque issue
Mine do this sometimes

Do you mean the Eccentric Shaft issue? I didn't think it was that sound.

[Graves]

Originally Posted by flo93100

Hello
It’s the exhaust camshaft torque issue
Mine do this sometimes

Yeah. That's exactly what I think it is. Guess my car is just one of the ones with the issue. My car just fell out of warranty. It's tuned though so I doubt BMW would fix it.

[saikumarmeka]

Originally Posted by Graves

Yeah. That's exactly what I think it is. Guess my car is just one of the ones with the issue. My car just fell out of warranty. It's tuned though so I doubt BMW would fix it.

Definitely sounds like the eccentric shaft/exhaust lifter issue. Had mine replaced at 20K, and now at 50K no issues at all. Attached is the parts list replaced.

[flo93100]

Some 5.0 mustang have this noise too
Liqui moly ceratec work good on the 5.0 to quiet the noise

[Graves]

Originally Posted by saikumarmeka

Definitely sounds like the eccentric shaft/exhaust lifter issue. Had mine replaced at 20K, and now at 50K no issues at all. Attached is the parts list replaced.

Don't see a parts list.

[Graves]

Noise goes away after driving it. Kind of thought it might. Have a shop checking it out anyway.

[saikumarmeka]

Originally Posted by Graves

Don't see a parts list.

I've attached it as a .pdf file to download.
File name "LINE OPCODE TECH TYPE HOURS".

[Graves]

Took it in and had it fixed. Turned out it was just the shitty 5w30 BMW oil. Cam follower was stuck. I moved from Germany to Georgia and the heat/humidity is just too much for that oil. The mechanic scoped the motor and it was just filthy from Dante's Inferno. Did a 4 stage flush and 10w60 and it purrs like a kitten. Zero issues now. The guy said he runs it in all his cars and his E30, E39, and E92 race cars. Oil he used was Rowe. He did a bunch of tests through black stone on BMW oil and others. He found Rowe worked the best. Seems to have helped.

[danyalsworld]

GravesI just picked up my f80 m3 comp last week and I just changed the oil change and started having same ticking issue, I just used 5w30 and started making this ticking noise on cold start but leaves after a few mins. What oil did you change too? I don’t have warranty so I’m just worried and stressed.

[Graves]

Well, just got done looking at everything as it was taken apart and there is not a damn thing wrong with it. Zero scoring, zero build up, gd thing is as clean as the day I bought it. However, I have the parts so the mechanic is going to put the new camshaft alley way, cam, and bolts in and see if that takes care of the issue. Weird.

[Graves]

Update: new camshaft and alley way in. Drove the car home 5 hours no issue. Cold started the car this AM, quiet as a mouse. The knocking is gone. I’m going to let it sit for a few days and cold start it and see what happens. But so far so good.

[aswy6]

What is a potential problem this may cause? My car has been doing this for like 5 years with many track days under its belt. When i go to track i usually dont get a noise for like a week or 2 but is there anything bad than can happen for not addressing it?

[Graves]

Originally Posted by aswy6

What is a potential problem this may cause? My car has been doing this for like 5 years with many track days under its belt. When i go to track i usually dont get a noise for like a week or 2 but is there anything bad than can happen for not addressing it?

Honestly, idk. Maybe just sooner wear and tear than normal. The shop I took it to said they have replaced a few so far. One was said to have been snapped in half and all it did was cause a misfire in the number 1 and 6 cylinder under load. I would gamble to say it would have gotten worse with more time.

Again, my cam and such looked fantastic.

[M3ANF80]

Just to add my 2 cents if anyone comes across this in the future who have this noise, I took apart the top end because mine started to do it (or I just started to notice it) and everything looked great with no odd wear. I ended up just putting it back together to spec following ista procedures using new bolts and gaskets for the required areas (cam bearing ledge, vanos wheel, spark plug well, injector seals, valve cover, etc.). That was all it took to fix the issue. It does require special tools which is a bit pricey if you don’t already have them. I thankfully already did from doing my crankhub so the job only cost me a few hundred. Although, because I didn’t see any wear I’m not sure how necessary it was to do it, the noise was just worrying.

[terahertz]

+1.

I had the same noise for a long time. I loosened and retorqued the exhaust cam bolts and the noise is totally gone.

I think the torque spec was 8nm and 60 degrees, but you can look it up in ista.

[papasmurf_m3]

So you went with 10w/60 oil instead of 5w/30 and it solved the issue?

I experienced more noise from the valve train with 40 weight oil. Went back to original weight and it's noticeably quieter.

Keep us updated!

[M3-TravelGuy]

I’ve been hearing potentially a similar sound coming from the engine. Opened up the hood and it’s certainly louder than inside the cabin. It seems to be coming from just left of the oil fill. Think this is them same? Pretty sure I’ve been hearing it for a while. But car drives fine. Out of warranty now so curious if it’s something that has to get fixed now or it’s normal. engine noise

[F80manz]

Edit: mine turned out to be my exhaust valves rattling all the way back to the engine bay. No issue with exhaust cam which was checked by my mechanic. Said everything inside looked perfect

I have also now discovered the same sound on my 19 F82 when not up to temp. Out of warranty and tuned so I have an appointment with the local euro shop right after Christmas. Will update with what the issue is. I'm assuming it's also the exhaust cam.