2010 MCS with 83k, manual

My car has been running well with no symptoms other than being told I need a new valve cover gasket. While beginning to ascend the Grapevine on my way into LA my car suddenly lost power and I was barely able to get it off the freeway.

When I came to a stop it basically stalled. I restarted it and it felt like it was misfiring and had a very rough idle. I didn't drive it any more and towed it to my buddies house where he ran his coder, a basic non-MCS scanner and it threw P0301 and P0302. We removed all of the spark plugs and they had the appearance of being fouled by oil and one even had the top part of the head broken off!

We replaced all of the spark plugs and got two new cores and put them in 1 and 2 (the two lateral cylinders). We also replaced the gasket and spark plug gasket.

Car is running the same! No improvement whatsoever.

I'm inclined to think my car needs the walnut shell treatment BUT my concern is that I experienced a SUDDEN loss of power, not a gradual decline like what I have read about most others presenting complaints.

Thoughts?

 

Have a picture of the plug?

Could have been pre-ignition going based off that.

 

Here is a picture of my spark plugs.

 

Could it be the piston skirt?

 

Damn.....pre-ignition will do that to plugs.

What cylinder did that plug come out of?

 

Or detonation, or mechanical damage due to foreign debris.


Which ever cylinder that came out of, I'd get that piston head checked, because that missing piece ended up somewhere......

And you say the car still runs rough correct?

 

It came out of 1.

 

I'm a friend of DrChinn working on his car, let me add some info.

Basic OBDII scanner only gives P0300,0301,0302... so multiple misfire and cyl1/2 misfire.

Valve gasket replaced, spark plugs replaced, 2 coilpacks replaced (and have been swapped in every order possible). No matter what, the code shows cylinder 1/2. My initial thought was he developed a bad coilpack(s), but I no longer thing there is a problem with the coils.

Next steps:
1) scan the car with a more powerful diagnostic tool (on the way) to see if we can tease out a mini-specific code, maybe a bad camshaft position sensor or something.
2) Run a compression test. My worst fear is the head gasket is blown, which would add up given that two adjacent cylinders are misfiring, but the engine hasn't been overheated. I don't know if mini HG's fail early, his car only has ~85K on the clock. Second fear is the flying metal from cylinder 1's ground electrode damaged valves in both cylinder 1/2.

I assume with the diagnostic software we can cycle the injectors and make sure they are working. But, any other ideas? I really don't want to pull the head unless there is a very good reason to do so. I checked all fuses in the main box, are there any relays that can cause either injectors or coilpacks to fail in this manner?

 

Pull the intake manifold and check the ports. Also possible high pressure fuel pump fault. I'm leaning towards carbon in the intake ports

 

I'm with NewCooperFanatic. The plug that is broken. That chunk went somewhere and that is the cylinder. You very probably have a piston that is damaged or cracked with other possible damage. Metal doesn't just dissapear and it's all fine. You may have a huge issue on your hands. I've seen smaller metal items cause same issues.

 

We did a cylinder compression test today.

Cylinder 1 = 0.
Cylinders 2-4 = ~165.

I think this is bad.

 

Now do a leak down test on cylinder 1, this will tell you where is leaking by.

 

What the chance that the pistons are alright?

The second gen R56 Mini Cooper S with N14 engines are well known for pre-ignition and/or detonation! If you have had your intake valves walnut blasted don't stop there because there's more carbon in the combustion chambers as well. Nothing 5 bottles of BG 44K can't handle.

Forgive my ignorance but how does one know which cylinders numbers?

 

We will be doing this Friday. I am curious why cylinder 2 is misfiring (based on our scanner, it misfires ~25% as often as cylinder 1) when it has equal compression to cyl 3&4. Obviously cylinder 1 has a serious issue, damaged valve, piston, or head gasket. But if it was a head gasket, I'd expect cylinder 2 to have a lower pressure.

Oh well, we'll see what the leak down shows Friday, but it looks like we are pulling the head no matter what at this point. Hopefully it's "just" a valve and not a piston with a hole in it.

 

I'm a BMW ///M guy, so all this talk of carbon and walnut blasting coming from you guys is very foreign to me haha. Not sure why this keeps being brought up.. it would be great if that was the issue... but considering an obvious piece of metal that went loose in the cylinder it seems unlikely to me. Has this carbon problem ever caused a cylinder to lose compression entirely?

Re: cylinder numbers. I forget where I found the info, but I found someone say physical cyl 1 is passengers side, and cyl 4 is drivers side. This adds up considering the OBDII code for cylinder 1 we have and the fact only one cylinder has bad compression.

 

Foreign to you.

Couldn't there be a small chance that the piston is cracked or weak to a point to where a visual examination wouldn't detect? I know aluminum is softer than what the valves are made of.

 

Yea, the M world has it's own issues as well of course.

There's a definite chance the piston could have a hole in it. I'm just hoping for my friend's sake that it doesn't and he can get by with just replacing a valve or gasket.

 

Question about head removal, you know that cam locking tool for locking the cams in place before replacing the timing chain assembly, if you remove the valves from the head how do you make sure that the pistons and valves are in sync when you're ready to reassemble?

 

You buy the cam timing tool: http://www.kochtools.com/index.php?p=product&id=103

 

That makes a valve job impossible if you can't remove the cams, I meant that if you wanted a complete restoration of the valve train and perhaps have the intake and exhaust port polished.

 

I think there might be some miscommunication. The tool I linked is used after re-installing the cams (if you removed them to replace valves or do P&P as you said). There's a different tool that actually locks them if you don't need to remove the cams, and I think is twice as expensive.