E70 50i engine off when driving, perplexed and needing suggestions

[Analyte]

Ok, I moved around it as quick as I could listening and I have to say it doesn't appear to be coming from the cats.

Again, only code is bank 1 pre-cat is saying too rich. Otherwise nothing else is showing.

Here's a quick video as I was looking and listening. With all the stuff out of the way, I have to say it seems to be coming from the valve cover area around cyl 1 or 2. So I guess that cover is now coming off.

Again, it's not a deep motor sound like a rod. It's high pitched and inconsistent. I would say it's a bent pushrod if this was my LS car

[Analyte]

Hmm, thinking out loud again. Does the Vanos tap without a rhythm when bad?

[Analyte]

Here's the link to the video. I was looking around trying to isolate it so sorry for all the movement. It appears to be from the front area, not heard from underneath at the oil pan, and the back of the engine by the cats not much there either.

https://youtu.be/55gdrGGZMZk?si=NOFPIMGI1Ij6xG6K

[ard]

OMG. I would not be running that motor. Not even for a little bit.


Your issue is not a air filter; not an O2 sensor; not a CAT.


Open up the timing chain cover. Look for bits. if you are lucky (and you dont keep running it and break a chain, crash the valvetrain) maybe you are lucky and new chains and guides will fix it.


It also doesnt sound like a vanos issue

[Analyte]

Timing chain and guides? Never heard one tapping like that before when bad, and this isn't my first BMW. Would I not be seeing cam position sensor faults if so? Not debating, just trying to learn since I never thought of chains/guides as a potential root cause.

I didn't realize the chains and guides were a concern on these N63, but I know my M62 can have issues.

If the guides are trashed, will they show bits in the oil pan like on an M62? I can drop that tomorrow easily. Thanks!

[80stech]

I don't know if it applies to these engines but on some the crankshaft timing gear is held in place by the front damper/pulley with only a small pin or key holding it in position till the pulley gets torqued, if the pulley comes loose the tiny pin/key partially shears and the engine goes out of time randomly until it swallows valves. So something else to check( pulley loose) and that is consistent with the sometimes hard cranking.

[ard]

Originally Posted by Analyte

If the guides are trashed, will they show bits in the oil pan like on an M62? I can drop that tomorrow easily. Thanks!

When I hear odd sounds - like metal bits- from inside an engine, my first instinct is to open up a path to the oil and have a look see.


I think your idea is a good one.


I have ZERO personal experience with your motor.



Years ago I had a Q45 V8 which I bought new. about 10 yeas and 150k in, I started hearing an odd ticking up front. Parked it. 6 monhts later, when I got around to it, found two broken valve guides- still enough there to prevent wild chain slap (and catastrophic failure). I was so so lucky. $2k in parts and I drove it another 150k miles.


GL!

[Analyte]

Well, I'm flying out today for work so this one will have to sit until I get time to jump back on it.

I didn't see any guide parts in the oil pan, and there is no metallic glitter in the oil. So at this point nothing is telling me anything truly negative. I reinstalled loosely in case I need another look before I'm done.

I got all the heat shields back on and covers so I don't leave it mess. Mainly I'll worry about forgetting where everything goes before I come back. I did pull the oil fill and peek in with a light and camera. The top bank 1 chain guide is still there in one piece so that doesn't appear to be it. Where I could reach there is still good tension on the chain so that's a plus that maybe the bank 1 tensioner is also still there.

I'll pull the valve cover when I return, and while I'm gone I'll do some goggle searches on removing the upper timing cover for a better look.

Thanks for all the help and suggestions so far. I'll update this thread when I get back on it in a few weeks. That will also give me time to order some gaskets to put it back together.

[Analyte]

Well, I heard from a fellow BMW owner that I should look at my HPFP just to verify it's ok as he said his made a similar tapping sound when it was going out. He first thought the engine went bad, but he had no video to share with me.

If it was a bad HPFP tapping, would it not be throwing codes? Just trying to rule this out for sure. I'm going to order some parts when I head back home, but I can't order everything. Lol

Anyone heard an N63 HPFP tapping when going out? If so, does it sound similar to mine or different?

[Analyte]

Ok, I also found this video and this does sound like my tapping sound. It's diagnosed as a rod knock in this video, and it doesn't start/stop like mine. I didn't see anything in the oil and pan, but it may be because she didn't drive it once it was heard.

https://youtu.be/FW42V5au7Vs?si=BuTN55tMDpiG8z9a

I'm just not seeing any knock sensor faults or anything else which is weird if this is it