Monday, January 27th, 2025 AT 1:09 PM
LARMOND25
- MEMBER
- 1999 JAGUAR XJ8
- 4.0L
- V8
- 4WD
- AUTOMATIC
- 197,000 MILES
Code P0305?
Code P0305, plugs seven and two have oil in well?
2 Replies
TOM STASSLE
- MEMBER
- 6 POSTS
If there is oil in the spark plug tubes you will need to replace the spark plug tube seals as well as the plugs and coil packs.
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Monday, January 27th, 2025 AT 2:34 PM
JACOBANDNICKOLAS
- MECHANIC
- 110,176 POSTS
Hi,
If you have oil in the plug wells, yes, the valve cover gasket will need to be replaced. The interesting thing is the misfire isn't in the cylinder that has the code.
Is there anything interesting or different related to cylinder 5's coil? For example, do you notice any gray marks on the spark plug boot that could indicate it is shorting? In what condition is the spark plug in that cylinder compared to others?
I attached a pic below showing the firing order and cylinder locations. In red, I indicated the cylinder related to the misfire. The highlighted ones are where you found oil. I'm doing this only to confirm we are on the same page.
If that is correct, switch the coils in cylinders 5 and 6 and clear the code. See if the misfire moves to cylinder 6, which would be a P0306. If it does, replace the coil.
Let me know if you plan to replace the valve cover gaskets (should be done).
Take care,
Joe
See pic below.
If you have oil in the plug wells, yes, the valve cover gasket will need to be replaced. The interesting thing is the misfire isn't in the cylinder that has the code.
Is there anything interesting or different related to cylinder 5's coil? For example, do you notice any gray marks on the spark plug boot that could indicate it is shorting? In what condition is the spark plug in that cylinder compared to others?
I attached a pic below showing the firing order and cylinder locations. In red, I indicated the cylinder related to the misfire. The highlighted ones are where you found oil. I'm doing this only to confirm we are on the same page.
If that is correct, switch the coils in cylinders 5 and 6 and clear the code. See if the misfire moves to cylinder 6, which would be a P0306. If it does, replace the coil.
Let me know if you plan to replace the valve cover gaskets (should be done).
Take care,
Joe
See pic below.
Image (Click to make bigger)
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Monday, January 27th, 2025 AT 7:21 PM
