Z4M S54 Sudden Massive Oil Leak While Driving

Coi · 07-31-2022, 07:28 PM

I think my vanos oil pressure accumulator broke in half if not worse.

Was driving the other day and noticed that the car suddenly started shaking at idle and the tone of the exhaust seemed different. Was driving spiritedly but didn't hit any potholes or debris. Car was smooth once moving if not a little bit louder than normal. There was no CEL or any other warnings on the dash. Didn't seem down on power or like revs were limited. No knocking or ticking sounds. I drove for about 5 mins like this on some slow streets, going less than 2 miles.

It started to smell oil and noticed little bit of smoke in the beam of the right headlight. I pulled over and shut off the car to see what it was. Oil was pouring out from the right side of the engine at an alarming rate. There was also a trail going back from where I stopped. I couldn't tell how long the trail was because it only became a steady stream in the last few feet. There was no low oil warning and no oil pressure warning when I turned the car off. Dipstick was dry, and the puddle ended up huge didn't look like 6 quarts. Oil kept coming out well after I shut off the car.

I came across this thread on Z4-forum where someone's vanos oil line falied so I suspected that to be my problem. I took a look today and the line is fine at the typical failure spot at the top so I traced it down with my hand and found that the bottom of it is hanging loose with half of the vanos oil pressure accumulator still attached to it. I can't currently jack up the car so I'm not able to see what it's like from underneath. I couldn't feel if the other half of the pressure accumulator is still there or not.

So is it possible my vanos oil pressure accumulator cracked in half? I can't find anything about this happening to anyone else. My other concern is that maybe there's a hole in the engine block in that spot due to a snapped rod but the car was driving relatively normally so that doesn't seem likely.

If the only thing that failed was the vanos pressure accumulator, is there a possibility of damage from oil starvation? Again, there was no oil pressure light when I turned the car off.

I'm having the car towed to a mechanic tomorrow. Every other issue it's had either I fixed myself or took it to my previous mechanic who no longer works on cars so I'm researching shops. Probably going to to go with VT Motorwerks in Pleasanton, CA.

Has anyone else experienced or heard of something similar happening ?

grannyknot · 07-31-2022, 09:13 PM

Whoa, sounds like you turned off the engine just in the nick of time.
Sure there is a chance of damage from lack of oil but you may have got lucky, see what your mechanic says, you might get away with just replacing the accumulator.

Would love to see some pics if you get a chance.

Coi · 08-01-2022, 04:08 PM

Quote:

Originally Posted by grannyknot

Whoa, sounds like you turned off the engine just in the nick of time.
Sure there is a chance of damage from lack of oil but you may have got lucky, see what your mechanic says, you might get away with just replacing the accumulator.

Would love to see some pics if you get a chance.

Yeah, I'm hoping that since I never saw a low oil pressure light I was just in time. The oil that came out was also very clean looking with no signs whatsoever of sparkles.

The only photos I have as of now are of the puddle. I can't see the broken accumulator from the top of the engine, only feel it. Will definitely ask the mechanic to take photos and send them to me once they get the car up on a lift. May be a few days until then though. I'll post them.

I spoke to a couple people familiar with S54s and they've never heard of pressure accumulators breaking in half, so that happening is a little worrying. Crossing my fingers there isn't more damage down there.

grannyknot · 08-01-2022, 08:23 PM

Quote:

Originally Posted by Coi

I spoke to a couple people familiar with S54s and they've never heard of pressure accumulators breaking in half, so that happening is a little worrying. Crossing my fingers there isn't more damage down there.

I have been working with s54's for about 5 yrs and I have never heard that one either.
Ask the mechanic for the old parts, would love to see what actually failed,
the accumulator holds 1500 psi anytime the engine is running so it could be a weld or a flaw in the metal.
Quite literally an oil bomb.

racerbruce · 08-02-2022, 08:40 AM

https://www.pelicanparts.com/techart..._Replacing.htm

Here's perspective.

Coi · 08-04-2022, 02:30 PM

So I had the car towed to VT Motorworks. They said the accumulator was fine, so I'm not sure what I was feeling when I reached down. It really felt like there was something sizable hanging loose at the end of the vanos oil line, but I guess not. Will update with pics when I have them. Apparently the right engine mount failed and the vanos oil line broke down near the bottom. The car needed 3 quarts of oil, but I suspect the majority of that leaked out after I turned off the engine.

When they turned the engine on after fixing the line the vanos was making a very loud clanking noise. It wasn't doing that when I turned the engine off. It's likely the vanos is internally damaged due to oil starvation. I just had it fully rebuilt after buying the car last year, so this is really bad news.

So motor mounts, engine mount bracket, and vanos oil line have been replaced. I also had them do RTABs w/shims since they were shot and that also requires an alignment. Including another vanos rebuild it's going to be a $4000+ bill. Oof.

Really didn't expect to be nearly $8000 into repairs/maintenece in my first year and a half of ownership, especially since I got a PPI and bought a <75k mile car with service records. Still needs more work done including rear pads/rotors, more bushings/mounts, and at some point rod bearings.

grannyknot · 08-04-2022, 03:21 PM

That's a hard pill to swallow. Still it might only be one component in the Vanos, the only thing in the vanos that I can think of that relys on oil for crucial lubrication is the needle bearings around the pump disc.

zed_fan · 08-04-2022, 08:08 PM

Wow that's just bad luck man. Could there be any other internal engine damage I wonder? Hopefully not but it seems like it's turning into a money pit now unfortunately. I'm imagining the engine mount must have completely flattened which caused the engine to go lopsided and damage everything in its path.

Good luck hope it's good news once everything is tidied up at the shop.

07-31-2022, 07:28 PM	#1
Coi First Lieutenant 289 Rep 323 Posts Drives: 21 X3 M40i, 07 Z4MR Join Date: Mar 2021 Location: Cal iTrader: (0)	Z4M S54 Sudden Massive Oil Leak While Driving I think my vanos oil pressure accumulator broke in half if not worse. Was driving the other day and noticed that the car suddenly started shaking at idle and the tone of the exhaust seemed different. Was driving spiritedly but didn't hit any potholes or debris. Car was smooth once moving if not a little bit louder than normal. There was no CEL or any other warnings on the dash. Didn't seem down on power or like revs were limited. No knocking or ticking sounds. I drove for about 5 mins like this on some slow streets, going less than 2 miles. It started to smell oil and noticed little bit of smoke in the beam of the right headlight. I pulled over and shut off the car to see what it was. Oil was pouring out from the right side of the engine at an alarming rate. There was also a trail going back from where I stopped. I couldn't tell how long the trail was because it only became a steady stream in the last few feet. There was no low oil warning and no oil pressure warning when I turned the car off. Dipstick was dry, and the puddle ended up huge didn't look like 6 quarts. Oil kept coming out well after I shut off the car. I came across this thread on Z4-forum where someone's vanos oil line falied so I suspected that to be my problem. I took a look today and the line is fine at the typical failure spot at the top so I traced it down with my hand and found that the bottom of it is hanging loose with half of the vanos oil pressure accumulator still attached to it. I can't currently jack up the car so I'm not able to see what it's like from underneath. I couldn't feel if the other half of the pressure accumulator is still there or not. So is it possible my vanos oil pressure accumulator cracked in half? I can't find anything about this happening to anyone else. My other concern is that maybe there's a hole in the engine block in that spot due to a snapped rod but the car was driving relatively normally so that doesn't seem likely. If the only thing that failed was the vanos pressure accumulator, is there a possibility of damage from oil starvation? Again, there was no oil pressure light when I turned the car off. I'm having the car towed to a mechanic tomorrow. Every other issue it's had either I fixed myself or took it to my previous mechanic who no longer works on cars so I'm researching shops. Probably going to to go with VT Motorwerks in Pleasanton, CA. Has anyone else experienced or heard of something similar happening ?
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07-31-2022, 09:13 PM	#2
grannyknot Captain 951 Rep 780 Posts Drives: 2008 Z4M coupe Join Date: Oct 2021 Location: toronto iTrader: (0)	Whoa, sounds like you turned off the engine just in the nick of time. Sure there is a chance of damage from lack of oil but you may have got lucky, see what your mechanic says, you might get away with just replacing the accumulator. Would love to see some pics if you get a chance. __________________ 2008 E86 M coupe
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08-02-2022, 08:40 AM	#5
racerbruce Brigadier General 3854 Rep 3,004 Posts Drives: 21 X3 & 13 335is E93 Join Date: Dec 2009 Location: Seattle iTrader: (1)	https://www.pelicanparts.com/techart..._Replacing.htm Here's perspective. __________________ Racerbruce
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08-04-2022, 02:30 PM	#6
Coi First Lieutenant 289 Rep 323 Posts Drives: 21 X3 M40i, 07 Z4MR Join Date: Mar 2021 Location: Cal iTrader: (0)	So I had the car towed to VT Motorworks. They said the accumulator was fine, so I'm not sure what I was feeling when I reached down. It really felt like there was something sizable hanging loose at the end of the vanos oil line, but I guess not. Will update with pics when I have them. Apparently the right engine mount failed and the vanos oil line broke down near the bottom. The car needed 3 quarts of oil, but I suspect the majority of that leaked out after I turned off the engine. When they turned the engine on after fixing the line the vanos was making a very loud clanking noise. It wasn't doing that when I turned the engine off. It's likely the vanos is internally damaged due to oil starvation. I just had it fully rebuilt after buying the car last year, so this is really bad news. So motor mounts, engine mount bracket, and vanos oil line have been replaced. I also had them do RTABs w/shims since they were shot and that also requires an alignment. Including another vanos rebuild it's going to be a $4000+ bill. Oof. Really didn't expect to be nearly $8000 into repairs/maintenece in my first year and a half of ownership, especially since I got a PPI and bought a <75k mile car with service records. Still needs more work done including rear pads/rotors, more bushings/mounts, and at some point rod bearings. Last edited by Coi; 08-04-2022 at 02:44 PM..
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08-04-2022, 03:21 PM	#7
grannyknot Captain 951 Rep 780 Posts Drives: 2008 Z4M coupe Join Date: Oct 2021 Location: toronto iTrader: (0)	That's a hard pill to swallow. Still it might only be one component in the Vanos, the only thing in the vanos that I can think of that relys on oil for crucial lubrication is the needle bearings around the pump disc. __________________ 2008 E86 M coupe
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08-04-2022, 08:08 PM	#8
zed_fan Private 21 Rep 70 Posts Drives: 2006 Z4MR, E60 M5 6MT Join Date: Jul 2020 Location: AZ iTrader: (0)	Wow that's just bad luck man. Could there be any other internal engine damage I wonder? Hopefully not but it seems like it's turning into a money pit now unfortunately. I'm imagining the engine mount must have completely flattened which caused the engine to go lopsided and damage everything in its path. Good luck hope it's good news once everything is tidied up at the shop.
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