N55 Metallic Rattle

d21spike · 03-17-2017, 09:09 PM

Trying to help someone out, I'm more familiar with the N54. Anyways, here is a 2011 BMW X3 35i with 90,XXX miles on it. Had a drivetrain malfunction when I got to it, traced it down to be a faulty VANOS solenoid. There are no longer any engine related codes being thrown. At idle oil pressure is around 38psi if I recall. As the video shows once revved up, there is a rattle present (also noticeable with the oil cap removed). VANOS bolt recall was done in 2014 and I also had the valve cover off, they are present and accounted for. The VANOS solenoid screens are clean and clear. Oil level is proper as well. Any ideas?

https://youtu.be/QlVVntU71U0

rich_mane · 03-17-2017, 09:23 PM

Possibly timing chain guide or tensioner? It pains me to hear you revving it like that hahah

Or maybe a vanos unit went bad due to the bad solenoid. Those are my guesses

d21spike · 03-17-2017, 09:27 PM

Quote:

Originally Posted by rich_mane

Possibly timing chain guide or tensioner? It pains me to hear you revving it like that hahah

Oh me too, this was all below 2k RPM and well I needed to show him as well as get my question across. I thought tensioner as well, although when I pulled on the chain while the valve cover was off I didn't get it to move much. The guide I'm inclined to believe wouldn't be the case. Similar to the N54 the guide doesn't get bolted firmly in place but instead sort of floats. Technically speaking, excessive wear in the guide should either throw timing codes or have the slack taken up by the tensioner.

On the topic of the tensioner, only thing I think of with that is if the holes for the oil got plugged up. Assuming they are like the N54, the holes are pretty small.

playground · 03-17-2017, 09:39 PM

Sounds like spun rod bearings.

d21spike · 03-17-2017, 10:02 PM

Quote:

Originally Posted by playground

Sounds like spun rod bearings.

Almost wish it were since it would make more sense, but typically the knock increases with rpm where as here it just comes on with rpm and almost sounds like something loose. At idle it's not really present, the video is a little deceiving in that. To me personally it sounds like lifters lacking oil pressure but I know that's quite unlikely.

playground · 03-17-2017, 10:16 PM

Quote:

Originally Posted by d21spike

Almost wish it were since it would make more sense, but typically the knock increases with rpm where as here it just comes on with rpm and almost sounds like something loose. At idle it's not really present, the video is a little deceiving in that. To me personally it sounds like lifters lacking oil pressure but I know that's quite unlikely.

Your right, the sound doesn't sound too consistent to be a rod bearing failure. it sounds like something rattling up top? have you tried to disassemble the engine from top to bottom yet? It's probably not a good idea to keep revving it, if a vanos bolt has stripped clean loose.

d21spike · 03-17-2017, 10:27 PM

Have done that as well...Have also run the engine without the serpentine belt to rule out the accessories.

vespa · 03-17-2017, 11:59 PM

Sure sounds like a rod bearing to me. And with the oil cap off it sounds perfectly normal -- they all make terrible noises when the cap is off.

bahn · 03-18-2017, 07:39 AM

Quote:

Originally Posted by vespa

Sure sounds like a rod bearing to me. And with the oil cap off it sounds perfectly normal -- they all make terrible noises when the cap is off.

I'm with vespa. Sounds like rod bearing failure. Idle mine is holding 45-50 psi of oil pressure.

bbnks2 · 03-18-2017, 04:27 PM

Edit: after listening to your video again and how the knock follows rpm I'd say that sounds like rod knock or something else broken.

I will say that now that we can log oil prensure I've been watching mine. I idle 38pSI and hold 80psi under load.

bahn · 03-18-2017, 05:42 PM

Quote:

Originally Posted by bbnks2

Edit: after listening to your video again and how the knock follows rpm I'd say that sounds like rod knock or something else broken.

I will say that now that we can log oil prensure I've been watching mine. I idle 38pSI and hold 80psi under load.

I idle 45 and 100+ at wot.

bbnks2 · 03-18-2017, 07:37 PM

Quote:

Originally Posted by bahn

I idle 45 and 100+ at wot.

And this right here is why we need to be able to log these things lol. 100psi sounds excessively high, but n55 can vary oil pressure so who knows. I'm going to go ahead and say my motor is just fine. Curious to know what the tables look like now though... id imagine dme would be throwing a code if my oil pressure was off by 20psi.

bahn · 03-18-2017, 08:31 PM

Quote:

Originally Posted by bbnks2

And this right here is why we need to be able to log these things lol. 100psi sounds excessively high, but n55 can vary oil pressure so who knows. I'm going to go ahead and say my motor is just fine. Curious to know what the tables look like now though... id imagine dme would be throwing a code if my oil pressure was off by 20psi.

Yeah it does seem high. I was able to figure out the correct conversion factor for the oil pressure set point table in Tuner Pro. Check out the DIY tuning thread.

bbnks2 · 03-18-2017, 10:29 PM

Quote:

Originally Posted by bahn

Yeah it does seem high. I was able to figure out the correct conversion factor for the oil pressure set point table in Tuner Pro. Check out the DIY tuning thread.

Just saw it. What oil are you running? Looks like it might be too thick... or something else :x

I appreciate you looking into that table. I was really worried about tracking the car without being able to log oil pressure and knowing what the dme is targeting!

Now I'll have data to reference for when I put a 26row back in too.

playground · 03-23-2017, 12:24 PM

the plugs look fine, N55's run lean always.

bbnks2 · 03-23-2017, 12:45 PM

Didn't see the engine pics first time around...

Are those metals shaving everywhere!?

bahn · 03-23-2017, 02:54 PM

Quote:

Originally Posted by bbnks2

Didn't see the engine pics first time around...

Are those metals shaving everywhere!?

Sure looks like it :X

houtan · 03-24-2017, 04:59 AM

Op, any updates?

playground · 03-28-2017, 04:13 PM

related noise http://f30.bimmerpost.com/forums/sho....php?t=1328263
?

bbnks2 · 03-28-2017, 06:32 PM

Quote:

Originally Posted by playground

related noise http://f30.bimmerpost.com/forums/sho....php?t=1328263
?

I linked to the same thread at first, but this is not the same noise. Go back and listen to ops video and then look at the pics he posted. This isnt just a vacumm pump clunking away at idle. Ops knock gets worse with rpms and there are metal shavings throughout the crankcase in the pictures. That is not normal.

STR8-6IX · 03-30-2017, 11:38 AM

I am almost certain that is a blown rod bearing.

03-17-2017, 09:09 PM	#1
d21spike New Member 34 Rep 27 Posts Drives: 2007 BMW 335i Join Date: May 2014 Location: PA iTrader: (0)	N55 Metallic Rattle Trying to help someone out, I'm more familiar with the N54. Anyways, here is a 2011 BMW X3 35i with 90,XXX miles on it. Had a drivetrain malfunction when I got to it, traced it down to be a faulty VANOS solenoid. There are no longer any engine related codes being thrown. At idle oil pressure is around 38psi if I recall. As the video shows once revved up, there is a rattle present (also noticeable with the oil cap removed). VANOS bolt recall was done in 2014 and I also had the valve cover off, they are present and accounted for. The VANOS solenoid screens are clean and clear. Oil level is proper as well. Any ideas? https://youtu.be/QlVVntU71U0 Last edited by d21spike; 03-17-2017 at 09:16 PM..
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03-17-2017, 09:23 PM	#2
rich_mane First Lieutenant 139 Rep 227 Posts Drives: 2011 E92 335i Join Date: Jan 2016 Location: S.FL iTrader: (1)	Possibly timing chain guide or tensioner? It pains me to hear you revving it like that hahah Or maybe a vanos unit went bad due to the bad solenoid. Those are my guesses
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03-17-2017, 09:39 PM	#4
playground Lieutenant 32 Rep 473 Posts Drives: M3 Join Date: Jan 2013 Location: North York iTrader: (0)	Sounds like spun rod bearings. __________________ Become like water my friend.
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03-17-2017, 10:27 PM	#7
d21spike New Member 34 Rep 27 Posts Drives: 2007 BMW 335i Join Date: May 2014 Location: PA iTrader: (0)	Have done that as well...Have also run the engine without the serpentine belt to rule out the accessories.
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03-17-2017, 11:59 PM	#8
vespa First Lieutenant 217 Rep 245 Posts Drives: 2011 335i Join Date: Dec 2014 Location: Thousand Oaks iTrader: (0)	Sure sounds like a rod bearing to me. And with the oil cap off it sounds perfectly normal -- they all make terrible noises when the cap is off.
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03-18-2017, 04:27 PM	#10
bbnks2 Colonel 1207 Rep 2,026 Posts Drives: 135i N55 Join Date: Jan 2017 Location: NY iTrader: (0)	Edit: after listening to your video again and how the knock follows rpm I'd say that sounds like rod knock or something else broken. I will say that now that we can log oil prensure I've been watching mine. I idle 38pSI and hold 80psi under load. Last edited by bbnks2; 03-18-2017 at 04:49 PM..
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03-23-2017, 12:24 PM	#15
playground Lieutenant 32 Rep 473 Posts Drives: M3 Join Date: Jan 2013 Location: North York iTrader: (0)	the plugs look fine, N55's run lean always. __________________ Become like water my friend.
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03-23-2017, 12:45 PM	#16
bbnks2 Colonel 1207 Rep 2,026 Posts Drives: 135i N55 Join Date: Jan 2017 Location: NY iTrader: (0)	Didn't see the engine pics first time around... Are those metals shaving everywhere!?
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03-24-2017, 04:59 AM	#18
houtan Colonel 707 Rep 2,448 Posts Drives: 2011 135i Join Date: Jun 2013 Location: socal iTrader: (17) Garage List 2011 135i [9.80]	Op, any updates?
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03-28-2017, 04:13 PM	#19
playground Lieutenant 32 Rep 473 Posts Drives: M3 Join Date: Jan 2013 Location: North York iTrader: (0)	related noise http://f30.bimmerpost.com/forums/sho....php?t=1328263 ? __________________ Become like water my friend.
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03-30-2017, 11:38 AM	#21
STR8-6IX Banned 536 Rep 2,825 Posts Drives: RWD 528i N52 Join Date: Nov 2016 Location: Toronto iTrader: (0)	I am almost certain that is a blown rod bearing.
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