lots of smoke if left for a few days

[Firebreather]

My 4th gen has a weird issue. Normally it's fine (except for the exhaust gaskets which make it sound a train) but if you leave it for a few days, then next start up there is loads off white smoke coming out of the exhaust and it runs really rough for a few miles. After that it clears and is all fine again, but usually those first few miles are me sitting in a traffic jam so it's not ideal. What could be causing it?

[bhm1712]

White smoke????

Hmmmm

Definitely not blueish?

White smoke could be confused with oil smoke which has a blueish hue to it and could be down to valve stem oil seals or worn valve guides. Over a few days the oil from the cylinder head top seeps down the guides and accumulates on top of the piston which is the burnt off when starting up and first few miles. If the seals and guides are worn to a certain degree you can normally see smoke when moving off from idle or when stepping on the gas after deceleration from high rpm ( high vacuum causes oil to be sucked down the guides into the combustion chamber)

With the above you would notice the oil level slowly dropping.

If it's truly white it could be actually steam caused by coolant entering the combustion chamber and being boiled off. The head gasket could have a minute leak which allows coolant to enter the chamber very slowly when not running which is then boiled off when starting up and could be causing the rough running until it is boiled off. I'd be inclined to say this is more likely as oil tends not to cause rough running unless it's really bad and fouling the plugs. Because it stops after warm up it might be down to the leak being so very tiny that it's not causing enough coolant to pass through to create steam when it's hot.

You need to do a few tests- get a coolant "sniffer" test done for starters. Check the plugs as well as you may see evidence of oil on them if it's valve stem or guides.

[thirdgen]

Don't leave it a few days

[SUPERCHARGEDGTA]

are oil or water/coolant levels dropping?

[Firebreather]

It is definitely losing coolant, so it makes sense that that could be it

I checked the oil and it's clean, and the rad is also clean (but a bit empty) so if it's just water getting into the engine through a head gasket leak, can that be fixed with head gasket sealer? Does that stuff actually work? I'd rather not get the whole engine taken apart!

[bhm1712]

It is definitely losing coolant, so it makes sense that that could be it

I checked the oil and it's clean, and the rad is also clean (but a bit empty) so if it's just water getting into the engine through a head gasket leak, can that be fixed with head gasket sealer? Does that stuff actually work? I'd rather not get the whole engine taken apart!

In my experience (no offence intended here) the head gaskets in a tin or bottle are not the right way to go. Ive heard of people having miracle fixes with it only to be stuck at the roadside 500 miles later, and ive also heard of people going for thousands of miles with it.

But.....you dont get head gaskets in a tin or bottle just like you dont get new rings in a tin or bottle. Its never going to be the same as replacing it properly.

if the head gasket has gone, its gone for a reason and that really needs looking at, whether its just as simple as a failed gasket, or as involved as a slight warpage in the head surface or bolts stretched etc. As an example a work mate of mine at imperail tobacco had a head gasket leak on his nissan x-trail the week before he was due to drive to Tolouse. His local garage suggested K-Seal and he went ahead with it. It seemed to fix the leak and there was no more coolant loss or steam in the exhaust. On the way back from France just before getting to calais im sure you can guess what happened....it failed and he had to get towed at great expense to the port and then relayed back to derbyshire in the UK by his UK breakdown firm.

[Firebreather]

I had a look today and refilled the rad. It only took about half a pint of water before it was full again, and I last checked it a few months ago so its not leaking quickly. Ive had a quick read up and it seems like the 3.8 has a common intake manifold/gasket issue (where its made of plastic and just warps) with similar symptoms to a head gasket. Could it be that? Or am I clutching at straws here? If it is the intake manifold is that an easier fix? What sort of cost would that be? And if it is the head gasket instead how much is that? Or is it time to get a new car if its the head gasket?

[SUPERCHARGEDGTA]

inlet is easier than head gasket (inlet has to come off if you do a headgasket)
headgasket is not that bad a job anyway

[Firebreather]

How bad is a head gasket then? I've always thought that the whole engine has to come apart and it costs a fortune? What would be a realistic cost to fix it then?