[Clammy]

Originally Posted by Explorerlyon

Pictures of my cylinder #5:

What is this right below the hole threads? This is in the 9'oclock position viewing from the passenger side. It did not move when I hand-cranked the engine.
Attachment 2628980
Attachment 2628981

See this Video for more detail:

The piston looks fine. Did you check to see if something is holding a valve open?

It never occurred to me to boroscope mine... already got the replacement engine, but I'm gonna scope the cylinder, and make sure I NEED to swap the engine. If it turns out I have something just jamming a valve open (such as the missing DISA flap I never found), I'll save myself lots of time and money!

Cheers!

[Explorerlyon]

I pulled the intake manifold off (hope to never do that again, wow, that was not easy).

DISA valve is destroyed. But where are the parts?


The center pin is lodged under the intake valve. But where is the flap? Cannot find any evidence of the flap in the manifold.


1. Do I just yank that pin out from under the valve? I don't want to cause any additional damage.

2. Can I run the car with the complete intake off? I would hate to put all the intake back together and find out I still have an issue.

3. Any other suggestions on putting all this back together now?

[Clammy]

Originally Posted by Explorerlyon

I pulled the intake manifold off (hope to never do that again, wow, that was not easy).

DISA valve is destroyed. But where are the parts?
Attachment 2629189

The center pin is lodged under the intake valve. But where is the flap? Cannot find any evidence of the flap in the manifold.
Attachment 2629190

1. Do I just yank that pin out from under the valve? I don't want to cause any additional damage.

2. Can I run the car with the complete intake off? I would hate to put all the intake back together and find out I still have an issue.

3. Any other suggestions on putting all this back together now?

Quite possible that the plastic flap got burned up, but you should probably scope the other cylinders to see if there's any plastic slag on top of a piston. You got LUCKY that the pin wound up there, instead of inside the cylinder. Hopefully, it didn't destroy the valve or seat. Not sure what the best way to remove it is. You'll need to hold the pin, and push the valve down to extract it.

There's no way to run the engine with the intake manifold off. You're going to have to put everything back together, and cross your fingers.

Once you get the pin out, run another compression test.

My large DISA looked like that when I pulled it out a few weeks before losing the cylinder, and I couldn't find ANY of the parts. I'm going to have the shop scope the #6 cylinder, and see if maybe the pin got into it, and punched the piston, or something else caused the loss of compression.

Cheers!

[smass]

Wow you got lucky with that pin. A few years ago, another poster a found that embedded in the side of the piston and needed a new engine. Your engine is going to be fine.
Remove the intake manifold bolts and try to pull the rear of the intake back and down enough to be able to pull that pin out. I don't think you need to completely remove the manifold. A hemostat should work to hold it. If needed, gently push down on the valve to release the pressure. If it falls in, a magnet should be able to remove it.

https://www.amazon.com/HTS-161S2-Loc...dp/B000W1Y9YU/

The DISA flap could be inside the intake. Borescope around and see if you find it. Or it could have been eaten by the engine months ago.

How many miles do you have on your 330i? I guess I need to consider replacing the 16-year-old DISAs in our 330i.

[Explorerlyon]

Originally Posted by smass

Wow you got lucky with that pin. A few years ago, another poster a found that embedded in the side of the piston and needed a new engine. Your engine is going to be fine.
Remove the intake manifold bolts and try to pull the rear of the intake back and down enough to be able to pull that pin out. I don't think you need to completely remove the manifold. A hemostat should work to hold it. If needed, gently push down on the valve to release the pressure. If it falls in, a magnet should be able to remove it.

https://www.amazon.com/HTS-161S2-Loc...dp/B000W1Y9YU/

The DISA flap could be inside the intake. Borescope around and see if you find it. Or it could have been eaten by the engine months ago.

How many miles do you have on your 330i? I guess I need to consider replacing the 16-year-old DISAs in our 330i.

Thanks. Miles are 198,000. My pin is plastic. I read somewhere they changed to a metal pin in later years The DISA that failed is the one on the outside of the manifold and I think can be checked and replaced without removing the manifold. There is another smaller one on the inside of the manifold that is only accessible by removing the manifold.

I took the manifold all the way already which is how I found the pin lodged.

Definitely replace yours before you end up with my situation