It was raining yesterday and I noticed the typical rainbow colouring of some of the water around my car. Couldn't tell there and then if it was a car body fluid leak or just the water going trough the engine and getting contaminated. Decided to move it, as I started it and moved it, when I got back to parking spot, rainbow coloured water was left behind, under the exhaust, under the exact middle of the car, and under the engine. Some 12 hours passed, the rain stopped, I went to check it, there was still rainbow colouring, had a drive around the neighbourhood, eventually a shiny trail I could see in my mirror disappeared (hence if it was accumulated water somewhere, it went away) I popped the hood and this is what's bothering me (google photos album)

The board computer claims "OIL OK" on engine start, and so does visual inspection of the dip stick (plenty of oil . I have a short outing later, and this will give me the perfect opportunity to monitor the oil further, but any advice is welcome.

Car: C4 petrol 2005

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    I cannot tell for sure, but from the pictures it appears there's a head gasket leak. In a lot of cars, there are oil passages which go up through the block into the head which can provide oil to the cam bearings. These passages are sealed by the head gasket. If your headgasket is not sealing completely, this could be the cause. I cannot tell exactly from the pictures as the angle doesn't show me exactly where the head meets the block. Commented Feb 21, 2016 at 11:45
  • @ᴘᴀᴜʟsᴛᴇʀ2 Given the answer, apparently you are correct. I can shoot a video later for you. Commented Feb 21, 2016 at 12:18

1 Answer 1


Just reading this forum post, it appears your issue is a very common issue with your engine type. There is a main oil galley which runs right up through that corner of the head. This feeds the various parts in the head which need oil. The head gasket tends to fail right at this corner, so you'll see oil leakage. With that in mind, you'll most likely need to get your head gasket replaced and possibly get your head machined (if needed ... your mechanic/machine shop can tell your for sure) to fix the issue.

It could also be (remote chance) that the front cam seals have gone bad or that the valve cover gasket is leaking. These are highly unlikely, but would be good to check out before you go to the expense of changing the head gasket.

It is also of note, if this minor leak doesn't bother you, you won't kill your engine by letting it leak. You'd just have to keep an eye on the oil levels to ensure the engine has enough.

  • Well fair enough, exactly the answer I was hooping for. Of course I'll get it fixed as soon as possible. Will issue by-daily oil-check until then. Thank you good Sir! Commented Feb 21, 2016 at 12:17

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