Blown Headgasket maybe?

[DSMTyson]

I'll try to describe this as best I can.

When I first start my car up in the morning, after about 1 minute of runtime I can start to see very vague puffs of WHITE smoke coming out of the exhaust and it increasingly get worse until it is more of a transparent white fog. But it then goes away after about a minute. But then comes back and goes away again.

After it warms up to operating temperature and I start driving the smoke will intermittently come and go for the first minute of driving, and then it will completely clear up. It was eating a little bit of coolant before this started happening, and since it has started to smoke randomly it has stopped eating coolant....Which has me really confused..

I was sure it was a blown headgasket, so I did a compression test because i've seen blown headgaskets will usually cause a drop in compression in 1 or 2 cylinders.


I did a hot compression test.
Comperssion was Cyl. 1: 144psi, Cyl 2: 137psi, Cyl. 3: 141 psi, Cyl. 4: 150psi.

Seems normal to me.

Can anyone verify that what I am experiencing is a blown headgasket? Or could it be something else?

 

[99gst_racer]

Puffs of smoke upon start up is often failing/failed valve stem seals.

 

[DSMTyson]

But wouldn't that cause blue smoke due to oil getting into the cylinders? This is white smoke. Which would mean coolant, right?

Sorry, I've never had to deal with coolant getting anywhere but on me or in my cooling system.

 

[99gst_racer]

Typically yes, but if you aren't consuming coolant, then you aren't consuming coolant. And I can't think of a coolant burn that only happens upon startup.

 

[DSMTyson]

Yeah, that makes sense.

So your're saying that when the valve stem seals are cold they get a little bit of blow by, and once its warmed up the seals expand it stops the blow by and it starts to run normal.

I'll keep an eye on it and see if it starts to drink coolant. If not, it looks like its time to rebuild the head and upgrade the internals.

_____________________________________________________

Edit: Is there any harmful effects of leaking valve stem seals?

 

[99gst_racer]

So your're saying that when the valve stem seals are cold they get a little bit of blow by, and once its warmed up the seals expand it stops the blow by and it starts to run normal.

Yup, it's pretty much on cold start-ups only and can puff lightly for a minute or so.

Is there any harmful effects of leaking valve stem seals?

Nothing major. You can consume a bit of oil, and/or leak a little exhaust into the crankcase, but if doesn't affect driveability much at all. A co-worker's Escort has had shot seals for 2 years now, and it's still doing just fine.

 

[DSMTyson]

Thanks a lot, man. I feel better knowing that I wont #### up anything by driving around.