E46 328i possibly blown head gasket?

godinman

godinman

godinman

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Hi All,

My E46 328i decided to fill a small country lane with impenetrable white smoke on the weekend, it started randomly going up a hill and stopped again after around 100m. It was properly thick steam/smoke and there is mayo in the filler cap but not in the water.

Does this definitely sound like the head has gone? It drove fine and I had to drive it home and it seemed fine then other than a small amount of vapour when revving.

Anything else it could be? I've read about the crankcase valve but apparently you should have suction in the dipstick (ooer) which this doesn't have.

Then engine hadn't warmed up properly when it did it, I'd probably driven around 6 miles.

The local garage said they'd do a sniff test on it, but would that prove the gasket had gone or just that water had mixed with the oil?

It was about a cup low on water, although I hadn't checked it for about 3 weeks so no idea when that happened, but it hasn't lost loads, all temps were fine and the engine sounded fine.

Thanks for any help.
 
That doesn't sound like a blown head gasket. Sounds more like it was burning oil for some reason. Is the oil level low?

Yes a sniff test will prove it one way or the other.
 
It was REALLY thick white smoke, if that makes any difference. :p I'll check the oil level tomorrow it was fine a few weeks ago. I don't suppose it would have burnt that much in a hundred meters or so. What colour is burning oil?
 
godinman said:
It was REALLY thick white smoke, if that makes any difference. :p I'll check the oil level tomorrow it was fine a few weeks ago. I don't suppose it would have burnt that much in a hundred meters or so. What colour is burning oil?
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Burning oil produces a white smoke with a very noticeable blue tint. Coolant entering the combustion chamber produces white smoke, with a distinctive sweet smell (assuming you have anti-freeze in the system).
 
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Never heard of an aos and can't find it on Google! It was clean, white smoke and there's mayo in the oil.. Didn't get out to sniff but will if there is vapour when I first start it.

Guess I'll take it in to the garage, mildly low on funds currently so fingers crossed it's something simple.
 
Dogbreath said:
Burning oil produces a white smoke with a very noticeable blue tint. Coolant entering the combustion chamber produces white smoke, with a distinctive sweet smell (assuming you have anti-freeze in the system).
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Depends how much oil it's burning, a little bit and yeah it comes out blue, but if it's a lot then it comes out pure white, and has a very strong oil smell.
 
Burnt oil will have a blue tint when it's cold. When it's warmed up and the cat is hot it will look white.

Is the mayo in the oil or just in the cap?
 
godinman said:
Never heard of an aos and can't find it on Google! It was clean, white smoke and there's mayo in the oil.. Didn't get out to sniff but will if there is vapour when I first start it.

Guess I'll take it in to the garage, mildly low on funds currently so fingers crossed it's something simple.
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air oil seperator, I only say because M3 has one and my M3 was drinking oil, changed this and now it does not use a drop, but I had no smoking. :)

Mayo on cap sounds like head gasket, though. :(
 
Gibbo said:
air oil seperator, I only say because M3 has one and my M3 was drinking oil, changed this and now it does not use a drop, but I had no smoking. :)

Mayo on cap sounds like head gasket, though. :(
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Mayo just in the cap is not an indication of the head gasket gone, mayo in the oil however is a possible head gasket failure.
 
Gibbo said:
AOS maybe, about £30 part and 10 mins to fit if your car has one that is.
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If you are referring to the CCV then I request the OP to drive to your place. I will bring the part with me and if you change it in 10 minutes I will personally transfer £50,000 to your bank or to a charity of your choice.
 
E46s are renowned for having mayo in the oil cap because of short journeys. Pull off the oil breather hose? See if that's sludged? May give you an indication.
 
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