Misfire on all cylinders on one side

[Skyline]

I have a bit different hypothesis. Don't get me wrong, low compression is very, very bad; but it might not be the cause of the misfire. What I'd like to know is:

What was the condition of the plugs you pulled from the low compression cylinders? Were they black and oil fouled or were they nice even grey?

Get one of those test probes that can detect coil pack firing and voltage, and see if at idle, they are all firing properly.

Did you try swapping the coil packs on the left bank with the coil packs on the right bank to see if the problem moved?

Assuming that the plugs look good, and swapping the coil packs does not move the problem to the other bank, I would start to think about a bad ground for the offending bank.

[SlickGT1]

I think you should get a second on site opinion.

I agree, your car would smoke if your rings were screwed. You might have a cracked block, but not sure how the vanes in the block are and where it would leak without mixing fluids.

Get a mechanic to take a look at that engine. Something is not adding up after all you have done. Don't sell it yet.

[SlickGT1]

Wait on a second note. I have a feeling your valves are shot. The fact that you hear air in the oil cap, not burning oil, and no compression in the two cylc, seems like your valves made out at one point with the cylinder.

The problem is somewhere in the head.

[Skyline]

Check out this site:

Coil On Plug Tester, Waekon COP Tester 76562

[mrathell]

Originally Posted by Skyline

What was the condition of the plugs you pulled from the low compression cylinders? Were they black and oil fouled or were they nice even grey?

I installed new plugs and after about 2 weeks of driving I pulled them and they were completely black on all 4 prongs, dry with no oil residue,

Originally Posted by Skyline

Did you try swapping the coil packs on the left bank with the coil packs on the right bank to see if the problem moved?

Yes, I swapped all coils from one side to the other with the same result staying on the driver side. I even pulled each plug to make sure it would fire when the ignition was turned on and they all did.

[Skyline]

Originally Posted by SlickGT1

Wait on a second note. I have a feeling your valves are shot. The fact that you hear air in the oil cap, not burning oil, and no compression in the two cylc, seems like your valves made out at one point with the cylinder.

The problem is somewhere in the head.

I think you've got that mixed up. The leakdown test pressurizes the cylinder. With valves supposedly closed. If air is leaking, it's generally going to come out in one of three spots; exhaust, intake, or down past the rings. If it goes down past the rings, think about where that air pressure is going to go to excape....

Bad intake valve....you'll hear air in the intake. Bad exhaust valve...air in exhaust. He did not experience either of these. Obviously there are other places that air could leak out, for example a blown head gasket.

[mrathell]

Originally Posted by SlickGT1

Wait on a second note. I have a feeling your valves are shot. The fact that you hear air in the oil cap, not burning oil, and no compression in the two cylc, seems like your valves made out at one point with the cylinder.

All 4 cylinders on the driver side were low. The front two were lower than the rear two but all four were low.

[mrathell]

Thanks guys, but what kind of issue can exist in this type of scenario?

It seems as all scenarios mentioned would result in oil burning, except for the "ground" reason suggested. I have to research on how to test for a bad ground on the ignition wiring. It would have to be a ground that is connected to all 4 cylinders while not connected to the passenger side bank.

What would cause misfire at idle but doesn't when RPM's are over 800?
What type of issue can go away by increasing RPM's?
What type of issue can exist in the above two questions while not burning oil?

[SlickGT1]

Originally Posted by Skyline

I think you've got that mixed up. The leakdown test pressurizes the cylinder. With valves supposedly closed. If air is leaking, it's generally going to come out in one of three spots; exhaust, intake, or down past the rings. If it goes down past the rings, think about where that air pressure is going to go to excape....

No I know how the leakdown test works, my logic is something else. He should be burning oil and smoking with bad rings.

Bad intake valve....you'll hear air in the intake. Bad exhaust valve...air in exhaust. He did not experience either of these. Obviously there are other places that air could leak out, for example a blown head gasket.

No I know how the leakdown test works, my logic is something else. He should be burning oil and smoking with bad rings.

But he did the shade tree test, and I am curious why he is not burning anything. Think of it like this. If his valves aren't sealing properly, and the stem seals are leaking, he would hear air in the oil cap. Remember, the oil cap is on the valve cover, and the valves are right under it.

Did you hear air in the dipstik tube by the way?

Can this be head gasket?

Has the car overheated at some point?

[mrathell]

Originally Posted by SlickGT1

No I know how the leakdown test works, my logic is something else. He should be burning oil and smoking with bad rings.

But he did the shade tree test, and I am curious why he is not burning anything. Think of it like this. If his valves aren't sealing properly, and the stem seals are leaking, he would hear air in the oil cap. Remember, the oil cap is on the valve cover, and the valves are right under it.

Did you hear air in the dipstik tube by the way?

Can this be head gasket?

Has the car overheated at some point?

It has never even came close to overheating. The X runs fantastic except for the misfire while idling.

The oil cap is on the passenger side and the leak down was on the driver side. I never checked the dipstick.


If it was the head gasket, we would have to say that the head gasket failed in two spots on the driver side, between the first two cylinders and also between the second two cylinders because all four were low.

Also no oil and antifreeze is mixing at all.