White cloud out of exhaust on start up?

[jerrysta]

Guys, in the last few days I have noticed anytime my car sits for more than a couple of hours, on startup it will smoke from the exhaust. The smoke is white and does not have an oil or coolant odor to it. If anything it smells like fuel. It is a pretty big cloud that only lasts for about 5 or ten seconds and then the exhaust is normal. Also, I checked my coolant level and it is full. Does not appear to be losing any. As I said, this only occurs when the car has not been driven in a couple of hours.

Someone mentioned a bad/stuck pcv valve that may not be recirculating unburned fuel and thus I am getting fuel vapors through the exhaust.

I am very nervous about this since any of you guys that have helped me in the past know that I am very much a novice. Any ideas? Could the pvc thing be right.

[soCalTA]

well from what you described .. the smell .. lenght of time, etc it does sound like you are seeing/smelling unburned fuel. I would start with the advice you got from another here on the board and follow that.

[wolfdogs]

both of mine did that, the hawk still does. condensation builds up in the exhaust from driving short distances.......

smells like fuel cause thats whats burned to make exhaust in the first place.

[jerrysta]

It was a friend of mine who told me that, not anyone on the board. I have found the guys on the board to be the most knowledgable out there. So, I wanted to see if that sounded right. It sounds like you think it could be the pcv valve, too. Thanks for the help.

[lt1fury]

usually white smoke can mean you are running lean also. change the pcv valve first. then go from there

[jerrysta]

Wolfman,

Anybody ever look at you like you were crazy when all that smoke came out?

I can picture myself in the staging lanes when it's time to run and starting it with all that smoke coming out!

I'll try changing the pcv valve and if that's not it, then I'll see if it goes away as the weather changes and it's less humid.

[Dave-S]

Another possibility is a leaky head gasket.

White smoke can be a sign of a leaking head gasket allowing coolant to get into the piston area. If coolant gets into the cylinder, it will vaporize and come out as steam when the car is started. Have you checked your coolant level lately? If it is dropping then that could be the culprit. A pressure test of the cooling system will tell you if there is a problem.

[jerrysta]

I noted in the post above that I am not losing any coolant, nor is there any coolant smell to the exhaust. That was my first fear as well.

[Steel2686]

Plus if it's just at start-up, it's not likely to be the head gasket as white smoke will usually come out whenever the engine is running. I'd try the PCV first, then go with Ken's suggestion of weather. See if anything changes.

[jerrysta]

Yeah it's only on start up. I'll try the PCV. Thanks.

[Rob B (shoebox)]

I noted in the post above that I am not losing any coolant, nor is there any coolant smell to the exhaust. That was my first fear as well.

It still could be a very small leak that is seeping into one cylinder during cool down. Once the engine heats up, the leak can "go away" do to thermal expansion of the metals. It only takes a little coolant to make some steam.

[jerrysta]

I've got two thoughts in my head......

1. It's the PCV. It's cheap and easy. Car's fixed, no more problems.

2. It's the head gasket....not cheap (if done at the shop) or easy (if done at home, over a weeks evenings of work) , but and this is a big but.....
if the heads are off why not get them ported along with the intake?

My friends dad is a skilled engine builder and can port the stock heads and intake for very little cash.

Can removal of the heads be done by a novice with the direction of a couple of skilled guys or does it require some real skill to do? If the car sits while this is done, that's okay. I have the time. I am more concerned about the actual difficulty or needing special tools.....

Thoughts?

[95TransAm]

Can removal of the heads be done by a novice with the direction of a couple of skilled guys or does it require some real skill to do? If the car sits while this is done, that's okay. I have the time. I am more concerned about the actual difficulty or needing special tools.....

Thoughts?

I've never pulled heads off an LT1 before....but, I have done it twice on an SBC 350. It's not the easiest of jobs, but by no means is it hard. The first time I pulled heads was about 2 years ago. At that time, I was regularly working on cars here and there for maybe 6-8 months. The second time I pulled heads was with my buddy this past February. We has all of his accessories, carb, intake, cam, headers, and heads off (with air tool assistance for 1 person at a time) in roughly 7 hours or so (including food, beer, and goofing around breaks).

For an LT1 I would think patience here is the key word. If you can turn a wrench decently and have patience, I think it shouldn't be too big of a problem. If you can, get another guy to assist, and I'd say you should have those heads off in a couple nights work.

[jerrysta]

It's not the PCV valve. Did it last night. The car still smokes.

I'm thinking of buying a block and starting to build it up from the bottom. Again, my friends dad can do work for me inexpensively. I've seen short blocks for around 300-350 dollars. It could maybe be a useful project for the winter. Also, the builder would let me pay for it in stages, as he does each part of the build, that way it's not a huge chunk up front. And we would have several months to get it done before next winter.