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Discussion Starter · #1 ·
I thought it was the plugs.. so I changed them.. one of my motor mounts was loose so I made it tight again and 300 miles later no misfire code or pending..

So today I noticed the pending fault code for 1 & 3 again.

I'm loss, I did a compression check on 1 & 3 and I had 180 PSI on both cylinders.

The plug wires are brand new Subaru cables.

I checked the coil pack and it came within spec of the service manual.
 

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96 Legacy OBW, EJ22 swap, 2" suspension lift, 215/75r15, HIDs, 06 WRX interior swap
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335 Posts
whats the coolant in your overflow bottle look like? sounds to me your right bank has a head gasket failure
 

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Discussion Starter · #3 ·
The head gaskets are fine I did them almost two years ago I have 180 psi on 1 & 3 with a compression tester.

I think it could be an issue with the coil pack because it seemed like the plug for cylinder 4 started to slip out and while it was still in it was enough to cause arc damage to the plastic body of the coil pack.. It still tests within spec however.
 

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01 VDC, 05 R Sedan, 06 BAJA EJ257
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I would concur with the coil pack being the problem. It could be failing after it gathers heat from the engine and it is expanding internally.
 

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^^ ditto

. . . it was enough to cause arc damage to the plastic body of the coil pack.
Normal resistance tests of the coil pack will not likely detect, nor be affected by, arcing paths through or along the coil case. However, when high voltage is being generated those arcing paths are like short circuits. If there's visible signs of arcing on the coil pack, it should be replaced.
 

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01 Outback H6 VDC, 97 GT wgn w/ ej22, 98 OBW w/ej22
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1,401 Posts
the coil usually fails, electrically at least, front and rear.
it is a wasted spark system and when it fires #1 it also fires #2.
if #1 has a bad coil misfire then #2 would as well.

that is not to say the physical connection to the coil on 1 & 3 are not very good.

swap the wires from one side to the other, see if the problem moves.
 

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There's two coils in each pack. One coil for the # 1 and 2 cylinders, and one for the #3 and 4 cylinders.

Cylinders 1 and 2 are on opposite sides of the engine, as are 3 and 4.

What is common in this case is that the high voltage towers (connections) for cylinders 1 and 3 are on the same side of coil pack. A crack in the case or signs of arcing in the area of the two high voltage towers could affect the firing of the #1 and 3 cylinders, while the #2 and 4 cylinders (on the opposite side of the engine) could still function.
 

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Outback 2.5 SE LPG Converted Non-Turbo 2006 56 Plate
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There's two coils in each pack. One coil for the # 1 and 2 cylinders, and one for the #3 and 4 cylinders.

Cylinders 1 and 2 are on opposite sides of the engine, as are 3 and 4.

What is common in this case is that the high voltage towers (connections) for cylinders 1 and 3 are on the same side of coil pack. A crack in the case or signs of arcing in the area of the two high voltage towers could affect the firing of the #1 and 3 cylinders, while the #2 and 4 cylinders (on the opposite side of theg engine) could still function.
I get intermittent misfire too but only on 1 and 3, how can test if it is indeed the coil pack?
 

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2001 VDC Wagon - White pearl - 302,000 km
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I get intermittent misfire too but only on 1 and 3, how can test if it is indeed the coil pack?
Like @plain OM said, resistance checks may not give an accurate representation of a working, hot coil.
Grab a used coil pack at the salvage yard and see if only one misfire code comes back.
 
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