[11b330i]

CAR: 2006 330i 6MT
MILEAGE : 152,000

So my car has been fine. Ever since i bought it this may, until 2 days ago. I stopped, filled up with gas, started the car, and kaput... Car is misfiring and ticking/rattling... Dumbfounded i got the car to my house and started delving into what it could be. Read a ton on the whole ticking issue with the n52 (which i never even noticed on mine before). This seemed like a lot more than everyone else's tick problem. All the videos i watched sounded nothing like mine. I got p0306 for cylinder 6 misfire, and the car sure was misfiring (as the video shows). So i decided to take the valve cover off and have a look inside. No major components looked broke, and everything looked pretty normal. Then i decided to turn the engine manually, it was then i heard the ticking from cylinder 6. Then i noticed it was coming from the farthest intake valve (last one to the firewall on cylinder 6) Then i realized i could just take the rocker right off (i think that is what it was, i'm not the worlds best mechanic, but i am pretty good if i say so myself) I attached the video of the rough idle and such and also what i believe to be the culprit. Thanks again for looking guys!

[Three_thirty_I]

Wow, at first it sounded to me like it could be a massive bearing knock! I hear a ticking which is very similar to a normal HVA issue, but then there is a slightly less consistent knocking sound which to me sounds like a typical bearing knock, and not sure if it's just the way the microphone is catching the exhaust note, but at 3000 rpm it almost sounds like the knocking/thudding is making the engine rumble?!

I am pretty sure you have found the problem with that rocker arm, so hopefully this will sort it out. But what has happened that it is doing this?

[11b330i]

no idea. Just started out of the blue. I was hoping to got it wasn't in the lower end, then i took off the valve cover and found that rocker arm was loose.

[mike-y]

maybe the lifter is stuck in the down position? the lifter should be pushing up on the other side of that rocker and make it push the valve down.. but if it's broke or stuck, it's not moving like is should.

either that or your rocker is broken.

[11b330i]

Could the lifter be stuck that bad? I'm going to do a compression test and leak down tonight or tomorrow.

[David0ff]

wow thats crazy
i also vote for a stuck lifter

[11b330i]

anyone of diagnosing this guys?

[David0ff]

^ rephrase without acoOhol

[Three_thirty_I]

How did the other lifters behave by comparison? In other words, if this lifter on cylinder six is stuck then the others would be operating differently. And judging by the car's age, this would most likely have the older head design? The one prone to the common noisy HVA issues? Mine still has this type, but so far the lifters are quiet, and to help prevent them from becoming problematic, I generally avoid short trips or trips where the engine does not properly get up to temperature - and engine gets driven hard at times so no shortage of oil flow through the entire engine!

[mike-y]

Originally Posted by Three_thirty_I

How did the other lifters behave by comparison? In other words, if this lifter on cylinder six is stuck then the others would be operating differently.

No, there are 24 lifters and they all operate independently. a stuck lifter won't affect the others next to it. if it did, they'd ALL be clacking.

[11b330i]

Ok. So, what I meant earlier was any ideas to "unstick" the lifter or to better diagnose that that is what is wrong here.

[Bmr3sn]

Important question, does the tick go away after driving for a bit? basically when the oil warms up, does the tick stop?

[11b330i]

No. Nt at all. It's still there. I mean the dang rocker arm is off the last valve.

[Three_thirty_I]

Originally Posted by mike-y

No, there are 24 lifters and they all operate independently. a stuck lifter won't affect the others next to it. if it did, they'd ALL be clacking.

What I meant is, how do the other lifters operate compared to this one that is presumably stuck?

[Delusive]

One of my friends who had an E90 N52 engine I believe had this noise before, made his car sound like a diesel. The noise didn't go away even after the engine was at operating temperature, couple weeks later he gave us news that his brake reservoir blew up and his engine died.

His mechanic said that his timing chain snapped, which was probably the cause of the ticking noise. He had to replace the whole engine, it's rare that I hear stories of timing chains coming loose in our engines.

[11b330i]

the timing chain is just fine. I assume the other lifters function just fine. Cylinder 6 was the only cylinder misfiring and the only one in which the rocker arm is so easily separated from the valve/spring.

[mike-y]

you are probably going to have to get into the head more and replace that lifter and maybe the rocker for good measure also. But I'm just speculating..

can you get it towed to a shop?

[11b330i]

i can get it to a shop, but its pretty clear that if anything in the head needs to be replaced i am better off buying a head from a newer model so the fix is in place and i won't have this problem again.

[11b330i]

trying to use this picture to determine how the rocker arm isn't exerting any pressure on the spring. Bent valve? Cracked Spring? Lifter stuck completely down or collapsed...

[11b330i]

if the rocker was say broken right after the lifter part, it would explain why the lifter isnt opening the valve, and why the top of the rocker is moving freely. The end of the video i grab the rocker and pull it up and to the side. Wouldn't it have to be broke in half to do that.

[David0ff]

99% you have a collapsed lifter

[11b330i]

Not sure if it is the lifters problem. I was able to pull up on the rocker arm and pull the lifter up with ease. i'll attach the video once it us done converting with vimeo's ultra slow upload process.


here it is