S50 wierd noise. Help Diagnose (vid)

[madjurgen]

one-way check valve in head?

[dude8383]

What's your oil pressure like at idle?

[BMW_TUNER]

I second the check valve. If it fails your sensor could see pressure and your cams no as much as needed.

[graphikg]

I second the check valve. If it fails your sensor could see pressure and your cams no as much as needed.

How do I check the check valve? and where is it?

What's your oil pressure like at idle?

And how do I check this?

It may also just be one of the rubber boots from my coil pack. One is ripper and may be sending electrical current off to the head and making it run poorly.

[graphikg]

You need to check each lifter to be sure that it is easily compressing and that it can draw fluid. If it can not you can remove the piston( gently) and clean the inner bore as well as sand the piston with 2000 grit. I did this on some of my sticky ones prior to reassembly. They now pump up and hold pressure perfectly. I had a link to a euro forum in the uk where the guy did a full write up. I am still looking for it. The only other thing that I have heard of happening is that the lifter gets destroyed in over rev situations because it pushed all of the fluid out and them bang the piston into the wall thus killin the lifter.

Look at what someone else told me in another thread... He said that the lifter has to be unable to compress easily.

"I also pulled my lifters and found a couple that were soft too. Going to replace them in mine and hope that cures the ticking. However, despite the ticking my car runs great."

Now I am not sure... Are lifters good when they are easily compressed - or not?

[DaveSmed]

Don't disassemble and sand your lifters. The tolerance on those is in the ten-thousandths range. If cleaning them doesn't fix it, if there's scoring, galling, or any bad stuff, you need new ones.

[madjurgen]

How do I check the check valve? and where is it?

Its on the bottom surface of the head, shouldve been replaced when doing the hg. Open your oil fill cap while the motor's running and see if you have oil spraying around inside the valve cover.

He said that the lifter has to be unable to compress easily.

+1 A new lifter will be very hard to compress.

[BMW_TUNER]

I will admit that I just cleaned mine I never had to sand them but I have read about and seen it done. 2000 grit is pretty fine.

[BMW_TUNER]

But the check valve is a likely culprit

[graphikg]

As an update... This is what the motor sounds like now. I think the Vanos just needed some oil pumped in it, since it was rebuilt and cleaned, and now the motor is much quiter. But it still runs badly and has power loss, and shakes a lot in the cabin. Thats why I put the camera in the dash for reference.

http://www.youtube.com/watch?v=1dAAnPqn0uI

[nrubenstein]

Have you confirmed that all cylinders are firing?

[Fusion]

That coil-head current idea is a pretty good one, I had that happen except with spark cables. Run it in pitch black dark and you should be able to see if its sparking outside.
Though I think the knock sensor should catch this and give a CEL?

[graphikg]

Have you confirmed that all cylinders are firing?

I havent confirmed that. Whats the best way to do that, because it kind of feels like that. Around 1000-2000 rpm the car rumbles a lot and feels smoother above those rpms; and I feel a significant loss in power.

That coil-head current idea is a pretty good one, I had that happen except with spark cables. Run it in pitch black dark and you should be able to see if its sparking outside.
Though I think the knock sensor should catch this and give a CEL?

I tried switching the coil pack rubber boot with one from my touring. The boot did seem a little different, but I tried it anyway and was the same.

[graphikg]

Would my car run with a rough idle, just because it has been disconnected from the system for so long? Meaning the DME has to re adjust istself to the car?

I bought new plugs and am going to see if that does anything.

[nrubenstein]

Measure the temperature of the header tubing. You can check for spark and fuel, but a cold (really, just noticeably cooler - it'll still get hot) tube is indicative.

And no, the car should not run roughly because the DME has been disconnected.