Cin2 is not present in the N51/N52 models.

[felix_okaforp]

2008 BMW 328i N51
N51 and N52 are nearly indistinguishable, in my opinion.


Suddenly began to malfunction. Cylinder #1 was found to have no compression.

I peeked inside and saw that one of the exhaust valves was ajar. Unharmed, undistorted.
Every other valve opens and closes when I turn the engine over, but this one.

I can almost feel the speculation starting, but has anybody else experienced something similar? Is it the valve spring that's damaged or is there another issue?

[kasper_youngq]

So, how wide is it? Are you able to quantify that?

Taking the valve cover off will allow you to examine the inside better.

[felix_okaforp]

Greetings, dear friend!
Here I am, dealing with N52, not long after I sorted out N62! Haha!


The valve is probably loosely open, maybe 2

Right now, I don't have the time to lift the valve cover since I have too many projects. I do that every day. For the time being, I will simply run it on five cylinders whilst I reassemble my N62 swap.

Just wanted to get the rundown from N52 owners on whether anyone has experienced this and whether it's a common problem or not.

Reassembling it in a damaged state is not something I am interested in doing.

I need a vehicle immediately, so disassembling it and waiting for parts isn't an option.
I can order the part—say, a valve spring—when it comes in the mail, and I can fix the N52 the same day if it's a common problem.

My main goal is to determine whether N52 engines have any characteristics with M62 engines that cause timing chain guides to fail.
You are already aware that timing chain guides would always break; disassembling M62 is unnecessary.

Mileage is 440k km, huh?

[kasper_youngq]

Good day. On occasion, our beasties behave in such a manner. They have late-night conversations and occasionally conspire. The "look at me" moment, however somewhat dramatic, occurred when your N52 became envious.

The mileage is rather high. There may have been a VANOS recall in the past, but the fact that there was just one valve that hung makes me doubt that it was that. If just one cam were to malfunction, it would be all or nothing. Ouch, that's almost at full stroke. I was hoping someone could tell me if a boroscope could look inside any valve covers. Sure, I can see why one needs a driver when the other is out.


Hopefully, the knowledgeable members of this community can shed light on your problem. Stay well

[joel_coxe]

I haven't heard any accounts of valves sitting open by more than a centimeter. With well around 200,000 kilometers on the clock, my 2008 328i N51 hasn't seen anything similar. That is terrible, though. I realize that having a car is necessary for driving. The engines' interference or non-interference status eludes me. If that is the case, you should exercise caution because my intuition tells me it is the first.

Without a doubt, the N52's timing chain guides outperform the M62's. It is likely that the seat or retainer of the valve spring is defective. The name slips my mind.