Misfire on all cylinders on one side

[SlickGT1]

Originally Posted by mrathell

Yes, I did, no leaks.

I will google the 'leak down' now.

Would you suggest running the compression test again using the oil in the cylinder trick to determine if its piston rings -vs- valve or head gasket. Or will the leak down help to achieve the same conclussion.

Leakdown test will help you find out what the hell is leaking. Use the end from your compression tester.

First crank your engine till you get to TDC. You can ratchet the crank bolt. Clockwise I believe. Stick a wire hanger into the plug hole, and mark the area where it comes up the highest. That will be your TDC. Valves should be closed at this time. Then connect that compression hose, and blow compressed air into the cylinder. Go to exhaust listen there, pop the oil cap, listen there, TB listen there, open coolant tank listen and watch there, you get the drift.

[TwinTurboGTR]

If he had a hole between Cyl 5 and 6 cylinder walls, he would get 0 psi right? Compression that low on two cyl has to be a fried valve or shot piston rings

[mrathell]

Ok I finally got the intake manifold off.

My intake manifold gaskets, valve cover gaskets and throttle body gaskets all arrived today.

The gaskets that were on there were original BMW gaskets but who knows if they were ever changed.

I will start putting it back together tomorrow and then I will rerun the compression test and do a leak down test as well.

Below are pictures after the intake manifold was removed.

Even though a vacuumed the engine and blew compressed air around the intake area before removing the intake manifold, plenty of debris still fell down in the intake ports.

To get it out, I first stuck the vacuum down in each intake port, then I blew compressed air in there and finished it out with another vacuuming.

So far me favorite tool would be the telescoping magnet.

[bastereo]

Low compression, yep leak down time.
You could do it with the intake off and have an easier time telling if it is the intake valves leaking.

No valve adjustment possible, it uses hydraulic lifters.

Adding a bit of oil to the cylinder and doing the compression test would be fine, but you already have the intake off and would need to redo the other side for a good comparison.
But, kinda pointless if you are going to do a leakdown.

I would do a leakdown before reinstalling the intake, because if you find leaking valves, the intake will just have to come back off.

[SlickGT1]

Agreed with bastereo 100%. Leakdown test that motor. Don't put it back together.

[mrathell]

Great guys thanks. I'll read up on it perform that within the next day or two.

I have the compression kit and an air compressor, so I believe I have the necessary tools.

[SlickGT1]

You do. YouTube. There is a guy that does a black suburban or something, he does it the way you need to do it. Compression tester and compressor. Just search leakdown test heads on, or not removed, or on engine.

[mrathell]

Originally Posted by SlickGT1

You do. YouTube. There is a guy that does a black suburban or something, he does it the way you need to do it. Compression tester and compressor. Just search leakdown test heads on, or not removed, or on engine.

Man, ive been search youtube a good portion of the day.......it was on the companies time so its ok

I couldnt find one that used a compression tester.

[SlickGT1]

I knew I would have to do this for you.

How To Perform A Leak Down Test - EricTheCarGuy - YouTube

[mrathell]

Update: First I want to thank all of you guys for your help


I performed the leak down test and everything appears to point to bottom end piston seals.

exhaust: did not hear air
antifreeze cap: no bubbles
intake vales: no noticeable sounds of air - driver side
oil cap: definite sound of air.

I put it all back together with new valve cover gaskets and intake manifold gaskets. I also re-tapped the bad threads on the driver side head, that was easy breezy, it took me all of 5 minutes.

Same issues persist.

I'm giving up at this point. I have zero plans on changing the engine. I'll just sell it and pass on to the new buyer my findings.

Now I'm asking you guys the experts these questions that just have been bugging me because they don't seem to add up.

1) If the rings on the pistons are so bad, wouldn't they be allowing for oil to enter the combustion chamber causing for me to burn oil with smoke coming out the tail pipe?

I haven't had to add oil even though I drive it 20 miles to and from work everyday.
Absolutely no smoke on start up or driving or idling.

2) Why does the misfire stop as soon as I begin to accelerate or increase the RPM's while in Park?

I would assume it would become worse as I drive but instead the issue vanish while driving.