[heze]

Good morning everyone,

the last week, I was very busy to find and solve a loud tick in my N55 engine. Please also listen/see the youtube movie which is included in this message.

The ticking sound frequency is exactly half of the crankshaft rotating frequency, which means that it should be generated nearby the camshafts.

Ticking noise is always present: cold engine, warm engine, low RPM, high RPM.

I was sure that one of the hydraulic lifters gone bad. I replaced all the lifters with used pieces from another engine (which ran very well before the rod bearing spun). This did not solve the problem.

I also changed both camshaft adjusters, from the same donor engine. This did also not solve the problem.

I checked all the rocker arms with the small bearings. Looks all ok.

I replaced all injectors with injectors from the donor engine. This did not help either.

I electrically disconnected the injectors one at a time, started the engine and observed the changes, and I discovered that when I remove the wire of injector 1, the ticking sound is gone.

I swapped injector 1 and 2 and tested again. When I electrically disconnect injector 1, the ticking sound is gone. This proves that the injector is not the problem.

I'm puzzled now. What is ticking in my engine? I opened the valve cover 3 times to check and replace, which is quitte a bit of work...

This engine (2012) is new in my car (E70 2010), and I converted the head from EURO6 to EURO5, which means that I needed to drill 6 additional threaded holes to accomodate the three old 'spark plug recess inserts' and the EURO 5 injectors.

I also replaced the vacuum pump to be able to install the 'old' HPFP (which is needed because the DME cannot control the newer version).

Please don't say that this is normal in a N55 engine, because people are staring at the car when I drive along... I can hear the ticking noise in the car while driving.

Does anyone has an idea what this problem can be?
Thanks in advance and best regards Hendrik.

The link to the Youtube movie

[E92only]

What is that mysterious ticking noise? Every time a thread like this goes up I remember this youtube video

Sorry, somebody please help this man.

[heze]

Good morning,

Is there really no one with experience in this matter?
In the mean time I tested also other vanos solenoids --> no change in behaviour after replacement.

Best regards Hendrik.

[TheGoodTheBadTheUgly]

All N55s have this sound if you listen carefully. The one from your engine seems to be louder though, but you shouldn't worry that much about it.

That cyclic noise is due to the fuel injected by the fuel injector at such high pressure. It is usually normal to have this sound.

If you feel like the sound is getting louder you might want to check your injectors.

[heze]

Good afternoon,

Thanks for your reply. I changed the injectors to be sure that one of them is not faulty.

The ticking noise is so loud that people are staring at the car when I drive along. This is certainly not normal behaviour. I had a N55 previously, and this engine did not have this tick either.

As you can already read, I checked a lot of things, and as far as I can see, the following points can be the problem:

- Camshaft sealing rings (for oil flow to the VANOS units), or the front camshaft bushing.
- tilting piston on cylinder 1 (explains why tick is gone when injector 1 is disabled).

I want to do a compression test on the first two cylinders and I also want to check the sealing rings on the camshafts. Are there other points I need to check?

Thanks in advance and best regards Hendrik

[TheGoodTheBadTheUgly]

Originally Posted by heze

Good afternoon,

Thanks for your reply. I changed the injectors to be sure that one of them is not faulty.

The ticking noise is so loud that people are staring at the car when I drive along. This is certainly not normal behaviour. I had a N55 previously, and this engine did not have this tick either.

As you can already read, I checked a lot of things, and as far as I can see, the following points can be the problem:

- Camshaft sealing rings (for oil flow to the VANOS units), or the front camshaft bushing.
- tilting piston on cylinder 1 (explains why tick is gone when injector 1 is disabled).

I want to do a compression test on the first two cylinders and I also want to check the sealing rings on the camshafts. Are there other points I need to check?

Thanks in advance and best regards Hendrik

I've personally always had this very noticeable ticking noise but not to the point where people can easily notice it when the hood is closed or while driving.

A compression test is super easy and might reveal some additional information. Just get a kit, remove your plug, thread the kit in, remove the fuel pump fuse and try to start the car for 6 cycles.

Like I read what you did and you covered pretty much everything especially with the lifters. I still think it's injector related.

[Dovydas.B]

I have the same sound from time to time. But I think its the leaky injector, because when I start the car after a night you can feel slight vibration in the cabin and a bit of fuel smell.

[heze]

Good afternoon all, I measured and checked lots of things now:

I did a compression test, and they all reads over 14 BAR (203 PSI).

I cut a hole in the valve cover and mounted it back. After starting the engine, I noticed that intake valve 2 (cylinder 1) was not moving while all the other valves were. This also explains why the tick was almost gone when I disconnected the injector of cylinder 1 (previous post).

To find the problem I swapped all the parts in the attached image between valve 1 and valve 2 and observed the new behaviour. The problem stayed on valve 2. Earlier, I swapped the excentric shaft, and the problem still stayed the same. Some first measurements does not show an abnormality on the camshaft...

The play on the rocker arms is quite much. I can also see it with engine off and valve cover removed: Turn the engine until the cam of the camshaft of cylinder 1 presses against the rocker arm. With a small allen key on the valvetronic motor, I can change the position of the exentric shaft. I noticed that valve 1 is immediately moving downwards after turning the excentric shaft, but valve 2 needs a number of turns of the excentric shaft motor before it is moving down.

This excessive play is causing the metallic tick in the engine. There is that much play present that the lifter cannot compensate for.

I think these are my options:
- Cam lobe damaged (could not see an abnormality, but it might be possible)
- Lifter hole in casting drilled too deep (the ticking should then be present since it was build)
- valve stem too short, valve not closing (cylinder compresses quitte well, so unlikely)

I'm determined to find the problem, but I'm more and more affraid that the solution would be a new cylinder head...

When somebody can give me input / experiences from previous cases, please feel free to post!

Thanks in advance,
Best regards Hendrik

[drwillb]

Wow, that's some troubleshooting you've done.

I just did my valvetronic actuator last week so I'm familiar with everything you're probing.

Best of luck with finding the actual cause.

[mhullihan]

OP, did you ever figure out a solution? Reading your post sounds identical to my e90 the way I bought it (newer head on an early n55) and all the fixes I've tried (new injectors, check lifters, replace cam seals) and I have the exact same noise.

I noticed when I started it the other day the noise goes away right around the time the thermostat needle moves off of the bottom temp. I'm wondering if it's an emissions thing. For example, if the cat temp needs to reach some minimum temp for the o2 sensors to see better numbers and then the fuel or evap system changes it's operation.

Anyway, really curious to here if you found a fix.

[Alimismail79]

Good Day! Newbie here!

Unfortunately my ActiveHybrid 5 N55 developed the exact same ticking noise as in the OPs Video. The noise is present at all times and the ticking frequency matches the Rpms. No error codes and no noticeable decrease in performance. My car is bone stock and was never really driven hard Only 68K Kms and services are carried at suggested intervals.

I took it to my local dealer and they thankfully said it isn’t a spun bearing and that it is something related on the top end. After many hours of research, this is the only forum that describes and sounds the same as my engine.

OP, have you resolved you issue yet? I am willing to try the injector test.
Do you simply unplug one at a time with the engine OFF and start and observe? Clear codes and repeat on the other 5?

Look forward to any response.
Many thanks in advance!

Edit: I would like to clarify that the noise I’m hearing isn’t the normal injector noise or wastegate rattle sounds. This is a new sound I’m hearing since recently.
Thank you

[heze]

It took about a year before I found another engine and I swapped the engines. The engine with the ticking sound was dismantled and I found a roller bearing needle of the excentric shaft standing upright in piston one. The piston was a bit deformed because of this and was ticking against the cylinder wall. I think a previous owner did a bad repair job on the excentric shaft, and after noticing the bad sound he sold the car to a scrap yard, and they sold the engine to me again (as being a good engine).

When you disconnect one injector, do this with the engine off. The ECU does not like it when you do this with engine running.

In your case it is also possible that one of the hydraulic valve lifters is broken. In most of the cases the tapping sound will go away after a few seconds after start...

Good luck!
Best regards Hendrik

[Alimismail79]

Hendrik, thank you for your response!
I am yet to try out the injector test but I’m curious to know, if the sound disappears after disconnecting the injector, would this confirm something has slipped inside the cylinder (like in your case)?

[nn7788]

I'm dealing with louder than usual noises on an N55 engine. Not the normal ticking noises from valve lifters or injectors.

I want to try the compression test and the injector disconnect test.

Same question, will the injector disconnect test show that something is inside the cylinder?

If I have no engine codes, what else could be the loud clanking/clicking/metal slapping noise? Gets louder if I take off the oil cap. But a mechanic said its not coming from the bottom of the engine.

[Alimismail79]

Originally Posted by nn7788

I'm dealing with louder than usual noises on an N55 engine. Not the normal ticking noises from valve lifters or injectors.

I want to try the compression test and the injector disconnect test.

Same question, will the injector disconnect test show that something is inside the cylinder?

If I have no engine codes, what else could be the loud clanking/clicking/metal slapping noise? Gets louder if I take off the oil cap. But a mechanic said its not coming from the bottom of the engine.

In your case, it maybe your timing chain, since it’s gets louder when you remove the oil cap.

Update:
Injector test didn’t help unfortunately. I’m starting to suspect it’s a lifter tick which I learnt is a common and thankfully less serious issue. However I will be sending it off to the garage for them to diagnose and possibly remove and clean/replace the lifters.
Cheers!

[heze]

Originally Posted by Alimismail79

Hendrik, thank you for your response!
I am yet to try out the injector test but I’m curious to know, if the sound disappears after disconnecting the injector, would this confirm something has slipped inside the cylinder (like in your case)?

When you disable the injector, there is less stress on this piston, since it does not get petrol. When the noise is caused by a tilting piston or connecting rod bearing play, the noise will get less loud when there is no fuel ignition.

In this test you are also testing the injector itself. When the sound is gone after disconnecting the injector, the injector itself is also a suspect.

Best regards Hendrik

[Alimismail79]

Greetings!
Apologies for not giving an update sooner.
I sent the car to a 3rd party garage and they diagnosed and fixed the problem. As suspected it was a faulty hydraulic lifter on Cylinder 6, one of the exhaust lifter. Unfortunately I was out of town during the holidays, so I couldn’t take any pictures of the insides of the engine for my curiosity. I do have the old lifter with me and it has no springiness so clearly something internal has broken. At just 70k Kms I am quite surprised this happened, but from a mechanical point of view, things can and will fail.
Thankfully the whole repair was a very reasonable price, doing the conversion, it’s equates to around $400 with the oil service included.
Cheers!

[Tallicia]

Thank you for the update Alimismail79 ! I have an occasional sound like this ticking and have suspected the lifters since I purchased it a couple months ago with about 130k miles on it.

Doing a Pro Lqui Moly oil flush helped it a good bit but not as perfect sounding as my other N55 Bimmer. After the flsuh, I have also added ceratec and I just added the hydraulic lifter additive-300ml and it is improving each day.

I just replaced the valve cover with an aluminum one and there was signs of sludge, though the flush likely got most of it. And any varnish was just wiping away, which is great to see how effective the flush is at breaking down old signs of deferred maintenance. I suspect as is far too often the case, bad oils, or far too infrequent oil and filter changes builds up sludge and it gets in places you really don't want it to be - like the lifters making them not work as they need to. I am going to do another flush in about 1 thousand miles and see how much more sludge/residue that it is able to get out of the lifters or any other actuators/tensioners/solenoids.

It would be absolutely fantastic if in these posts, posters would add just a few simple additional pieces of info when noises arise or things break. 1. How many miles on the engine. 2. When was the last 3 oil changes and what oil/additives. 3. What maintenance has been done since the 3rd previous oil change.