[JonEQuest]

I just bought a 2011 335i with N55 engine a couple of hours ago and have not had time to look in the engine yet. According to the guy I bought it from the car ran great until his son let it sit for 3 months when he was out of state. Then when he came back and started it the car now has a very distinctive engine knock. The engine sounds like it needs to be rebuilt and maybe it does. But has anyone heard of this happening before? The only theory I have is that one of the cam phasers slipped on the cam or the camshaft just broke when it was started. Possibly because of the engine sitting for a few months a cam was tight or maybe a lifter got stuck? The former owner said that because the "damage" suddenly appeared when they started it and not while driving it on the street, they thought it was a bad starter, so they put a new starter in trying to fix it. I know that sounds ridiculous, BUT the car came with another starter sitting in the trunk. So that makes me believe that the engine problem really did happen right on start up after sitting for a while. It does start right up but I towed it to my house to avoid causing further damage.

So has any one heard of an engine jumping time or breaking right a cam or something on start up after sitting for a while? I did start it up and with Torque I found misfire codes on cylinders 4, 5, 6 and P045B and P052B which is "Cold start camshaft position timing over retarded BANK 1" for the A+B camshafts.

[Pladi]

Originally Posted by JonEQuest

I just bought a 2011 335i with N55 engine a couple of hours ago and have not had time to look in the engine yet. According to the guy I bought it from the car ran great until his son let it sit for 3 months when he was out of state. Then when he came back and started it the car now has a very distinctive engine knock. The engine sounds like it needs to be rebuilt and maybe it does. But has anyone heard of this happening before? The only theory I have is that one of the cam phasers slipped on the cam or the camshaft just broke when it was started. Possibly because of the engine sitting for a few months a cam was tight or maybe a lifter got stuck? The former owner said that because the "damage" suddenly appeared when they started it and not while driving it on the street, they thought it was a bad starter, so they put a new starter in trying to fix it. I know that sounds ridiculous, BUT the car came with another starter sitting in the trunk. So that makes me believe that the engine problem really did happen right on start up after sitting for a while. It does start right up but I towed it to my house to avoid causing further damage.

So has any one heard of an engine jumping time or breaking right a cam or something on start up after sitting for a while? I did start it up and with Torque I found misfire codes on cylinders 4, 5, 6 and P045B and P052B which is "Cold start camshaft position timing over retarded BANK 1" for the A+B camshafts.

does the sound come from top or bottom of the engine ?

[Turbod]

Originally Posted by JonEQuest

So has any one heard of an engine jumping time or breaking right a cam or something on start up after sitting for a while? I did start it up and with Torque I found misfire codes on cylinders 4, 5, 6 and P045B and P052B which is "Cold start camshaft position timing over retarded BANK 1" for the A+B camshafts.

Bours had his timing jump but you would need to ask him for the details.

[JonEQuest]

The intake cam appears to have showed up early to the party. It is ahead a few teeth on timing. Probably slipped the bolt since they don't have a key or dowel pin. I also noticed a piece must have broken off of the plastic chain guide by the exhaust cam.

[Pladi]

So did you buy this car cheaper knowing it had a major issue or did this happen after the purchase ?

[bbnks2]

top of the chain guide rail won't affect anything.

Would a Cam slipping only a few degrees like this cause a knock, as in, valves hitting pistons? I was under the impression it would take being out of phase significantly more than this to damage valves. If there is a distinctive knock then maybe you have multiple issues here. I would pull off the #5 or #6 intake cam cap and check for destruction. It might be seized up from a dry start after sitting for a while.

[JonEQuest]

I bought this car with the assumption I may need a whole engine rebuild or replaced. With that said I think it may be a fairly easy fix. I think the cam phaser must have gotten stuck and didn't return to normal timing as it should. I am not sure if I should get another one or clean and test this one.

[bbnks2]

Originally Posted by JonEQuest

I bought this car with the assumption I may need a whole engine rebuild or replaced. With that said I think it may be a fairly easy fix. I think the cam phaser must have gotten stuck and didn't return to normal timing as it should. I am not sure if I should get another one or clean and test this one.

I can send you a used one to try for like $60. They are pretty expensive new. What does the cam do if you rotate the engine?

[JonEQuest]

Thanks but I went ahead and ordered a pair of aftermarket ones for $170 last night. The dealer wanted about $565 with a discount for just the intake one. I found that the spring had worn into the outside of the cover on the old one plus there appeared to be some wear on the inside as well. Taking one apart was kind of nice way to see how they work. I think the groves the spring wore into the outside stopped the cam from springing back to normal position when the oil pressure stopped.

[JonEQuest]

Update #2
After a lot of wrenching I pulled the sub frame, steering rack, oil pan etc. off and I did find some grey sludge in the bottom and a few gold flakes in the oil pan as well. I found the same amount of flakes in my N54 oil pan when I rebuilt it due to a bent rod and the rod bearings were actually in good shape. But because I am here already I am going to go ahead and replace all the rob bearings too. It takes so long to get the oil pan off that if you do it, you may as well change those bearings while your down there. Plus there is a decent chance one of mine bad anyway after finding what appears to be aluminum grey powder in the bottom of my oil pan. I did find the spring had worn into the cam phaser body which is made of aluminum so that could be the source of the grey but like I said. for $100 in bearings and about $30 in bolts it makes no sense to not do it.

[fatty335]

Originally Posted by JonEQuest

Update #2
After a lot of wrenching I pulled the sub frame, steering rack, oil pan etc. off and I did find some grey sludge in the bottom and a few gold flakes in the oil pan as well. I found the same amount of flakes in my N54 oil pan when I rebuilt it due to a bent rod and the rod bearings were actually in good shape. But because I am here already I am going to go ahead and replace all the rob bearings too. It takes so long to get the oil pan off that if you do it, you may as well change those bearings while your down there. Plus there is a decent chance one of mine bad anyway after finding what appears to be aluminum grey powder in the bottom of my oil pan. I did find the spring had worn into the cam phaser body which is made of aluminum so that could be the source of the grey but like I said. for $100 in bearings and about $30 in bolts it makes no sense to not do it.

JonE, please post up some pics of the bearings when you liberate them from the engine; those of us who have tracked bearing wear in the N55 would appreciate the info. Also, how many miles are on this engine? Do you plan to replace the bearings/bolts with OE or something else?

[ptpending]

no magic with n55, oil is changed by bmw interval or later and problematic oil pressure regulator valve (advancement of the n55 over n52 and n54) design of which was changed in 2012

[Pladi]

Originally Posted by ptpending

no magic with n55, oil is changed by bmw interval or later and problematic oil pressure regulator valve (advancement of the n55 over n52 and n54) design of which was changed in 2012

What valve is that where is it located can you point us to a part number ? This is the first i am hearing oil loss due to a valve issue..

[JonEQuest]

Originally Posted by fatty335

JonE, please post up some pics of the bearings when you liberate them from the engine; those of us who have tracked bearing wear in the N55 would appreciate the info. Also, how many miles are on this engine? Do you plan to replace the bearings/bolts with OE or something else?

This one has 105,000 on the clock. I already have some King brand rod bearings arriving tomorrow for $100 from Summit racing and I am using the stock BMW bolts that I am just going to pick up from the dealer for about $30. I also have to pull the oil pump to get to Cyl #1 so I had to get that bolt set too for about $23. This really is not a hard or expensive job when you have the car apart. The hard part is all the BS you have to go through to get there. Dropping the steering rack, tie rod ends, sway bar, control arms etc. then you can pull the sub frame and then there is almost 40 bolts to get the oil pan free including having to pull the belt so you can remove the power steering pump, etc. etc. After all that the rod bearings are a piece of cake. This is my second time doing this job on a BMW. The first was on my N54 which looks identical in the bottom end to this one. Even the rod bearings are the same part from King. My worry is that I have found some shards of copper metal material in the oil pickup tube and oil pan as well as a fine grey (probably aluminum) sheen in the bottom of the oil pan. There was a lot of wear on the intake cam phaser body from the spring rubbing on it. So that probably explains the aluminum. The other copper color shards are likely a bearing. I am thinking I may need to take apart the intake cam to make sure those bearings are OK as well. It just sucks that it costs money to look at anything since you ALWAYS have to replace the bolts at a few to several dollars a pop.

[ptpending]

Originally Posted by Pladi

What valve is that where is it located can you point us to a part number ? This is the first i am hearing oil loss due to a valve issue..

if you got N55 you need to have this PDF as table book

https://f15.bimmerpost.com/forums/at...0&d=1435890258

[JonEQuest]

Originally Posted by ptpending

if you got N55 you need to have this PDF as table book

https://f15.bimmerpost.com/forums/at...0&d=1435890258

LOL, I just downloaded that a couple of hours ago. Looks like the complicated the upper end to get .05% more efficiency and performance which seems to make them break more often than the N54.

[JonEQuest]

P.S. Has anyone removed and reinstalled the intake camshaft before? I am going to open it up and take a look at the bearing since something caused the intake phaser to jam and wear weird. I want to make sure there is not some trick to setting the valvetronic a certain way when you put the cam back in, etc.

[Pladi]

Originally Posted by ptpending

if you got N55 you need to have this PDF as table book

https://f15.bimmerpost.com/forums/at...0&d=1435890258

oh oki yes i remember now its the pressure control valve and its electronic. Thanks.

I have seen the book many many times before but could not recall.

[Pladi]

Originally Posted by JonEQuest

LOL, I just downloaded that a couple of hours ago. Looks like the complicated the upper end to get .05% more efficiency and performance which seems to make them break more often than the N54.

they did alot for the sake of "efficiency". Including putting a electronic water pump that keeps the oil temp to 250 deg..

[9krpmrx8]

smh.

[ptpending]

the whole thing with oil deficit in N55 is that crankshaft shells eat crankshaft or bake to it
so you have to replace crankshaft, and full rebuild will cost more than engine from junkyard
that's why n55 are sold quickly at junkyards
the positive thing is that camshafts and it's bed from N55 compatbile with N52 and N52 has problem with camshafts ate it's bed, so n52 owners happy to buy camshafts from n55 owners

[bbnks2]

Originally Posted by Pladi

oh oki yes i remember now its the pressure control valve and its electronic. Thanks.

I have seen the book many many times before but could not recall.

I've never heard of any kind of failure associated with the oil control valve. It's basically a vanos solenoid. Pretty simple device actually. If it fails it just means MORE oil pressure will be delivered to bearings rather than bypassing to the pan to reduce pumping losses. Oiling is actually simplified with the N55.

The electronic water pump is actually pretty awesome and has more than adequate flow. Ability to continue cycling water after the engine has shut off (turbo timer) and ability to control cylinder head temps for different driving conditions. Actual oil and water temps have more to do with DME logic than it does the pump itself. I have all stock components and my car sits at 210-220f oil temps... 180-190f coolant temps. What's wrong with the coolant pump? Cost and high failure rate is probably the only reason why they did away with it...

I honestly don't believe that N55's have any more oil related failures than N54. You just don't have N54's being serviced by shops anymore since they are essentially $7k third owners cars at this point... You scrap a car like that when it blows up. N55/N54 in general produce lots of low end torque which = high wear on the bearings.

I also don't believe the Teflon seals BMW switched to with the N55 completely solve the intake cam oiling issues. I think it helps prevent the seal from eating into the cam ledge but now how long does a Teflon seal last before it gets deformed or stretched out and causes the same issue?

JonEQuest To check the intake cam, just remove one of the caps. check the wear. Replace the cap using exact torque specs or you can cause the intake cam to bind up. Then check the next cap... no need to remove the cam altogether. That is a ton of extra work. If you do want to tear it all down, the only thing you really need to keep in mind is that you want the engine locked at TDC and install the cam with the label facing up. This ensure you don't mash valves into pistons. Read up on newtis.info.