[Tambohamilton]

Can anyone provide any further insight or opinion of my oil analysis report, please?

140000mi M57 330D. Engine has started knocking audibly over the last 1000mi or so, which I'm about to start trying to chase down. No errors, no symptoms besides the noise. Most audible around 1200rpm. It noise is directly with engine RPM - not half speed like timing chain noise, etc.

I haven't done any diagnostic work yet. First up is removing belts to rule out ancilaries and the harmonic damper. I'll also make sure the injectors are all tight. I need some clear weather before I can get into it though!

Thanks

[robnitro]

Looks good, pb, sn, and cu would be bearings.
Boron is ok, some oils use it.

[Tambohamilton]

Awesome, thankyou! I guess I'll have to look elsewhere for the source of the knock then...

[robnitro]

Originally Posted by Tambohamilton

Awesome, thankyou! I guess I'll have to look elsewhere for the source of the knock then...

Is it louder with oil cap off? That can be the vacuum pump too

[Tambohamilton]

I don't think so, no.

It is intermittent though; sometimes I start the engine and it's noisy - not particularly noticeable at idle, but a definite knock around 1200-1500 rpm. The next day it won't do it...or maybe it will. I'm pretty confused by that symptom.

It does it all the time (if it's doing it); driving/stationary, in gear/not in gear, etc.

Any suggestions which might match those particular symptoms?

Thanks

[robnitro]

How are your injector balance numbers?
They should be +-5 at idle. Also check the numbers while in D at idle. They'll be a little higher but share those too.

How's your mileage and are you deleted or stock?

[Tambohamilton]

Is injector balance the same as 'selective mass adjustment' in INPA? Those values are all good; +0.46/-0.48, maximum. Manual box here, so can't give them when in D.

140k miles, everything still intact, no tune; stock engine.

[turbotel]

Dual mass flywheel noise perhaps ?

[Tambohamilton]

I don't think so; does it in neutral as well as driving...noise doesn't seem to chsnge. But it could be; I know the dmf is a bit rattly because it does clatter a little on some low speed gear changes.

[robnitro]

Originally Posted by Tambohamilton

I don't think so; does it in neutral as well as driving...noise doesn't seem to chsnge. But it could be; I know the dmf is a bit rattly because it does clatter a little on some low speed gear changes.

Does it change when you push clutch penal in? My vw tdi had a noisy flywheel which would sound like rattle which got quieter with the gearbox disconnected.

[Tambohamilton]

I don't think it does. I did fiddle with the clutch a bit as I was driving along the other day - it occurred to me that maybe it was the release bearing or something - but I didn't notice any change. That said, I didn't push the clutch to the floor so I'll have to try that next time I'm out.

Thanks all for the help so far!

[Tambohamilton]

Well, a year later and I've got pretty good at ignoring the noise. So much so that I can't remember if it does it any more. I tightened the injectors recently, and I honestly can't remember if I've heard it since. Had another uoa recently which came back clean too.

Clearly I'm going mad here, because I swear someone in this thread had suggested a cracked exhaust manifold? A couple of times recently I've smelt my own fumes when I've parked up or been sat with the engine running...both times the engine and DPF should have been warm enough to be less stinky.

Was I imagining that a cracked manifold could cause these noises? Is that even a possibility on an M57T2 with (I think) a cast manifold? I also feel like low end response is lacking, which would agree with a leak upstream of the turbo.

Thanks again for any help!

[Nadir Point]

I got new hearing aids a few months ago after losing the last ones a month or so before that. One had been under-perfoming for some time and then I left the good one in a hotel room in Texas. I'm still getting used to all the noises my cars make. Again.