I have a 98 Protege that smokes quite a bit when you first start it up and only after it has been sitting over night and the outside temperature is cold. The smoke clears up after about 10 or 15 seconds and then it does not happen again through out the day. It also does not occur when the temperatures are warm only when its cold at the first start up.
It's a bluish colour smoke.
Any ideas?

 

how many miles on the engine, is it an sohc or dohc and what kind of tune care has it had?

 

What you have is oil backing down a cylinder when the car sits. You could pull the plugs and find which ones are oil fouled. That will tell you which cylinder it is. Compression test will tell you if it is really bad. Probably a dirty valve or two. Isn't alot you can do without throwing a pile of cash at it. What you might want to try is an old trick we used to try back in the carburetor days. Take out on the highway and give it a good run. Get the revs up near, but not over, the redline.

 

Sandeeeg its a dohc the car has 255000kms or just over 159000miles.

thanks MazdaES I just did a complete tune up on the car a few months ago but I will check the plugs and do a compression test, I have to replace the valve cover gasket so I will have the valves checked as well.
I was gonna run a few a bottles of seafoam through the car and then I will take it out on the highway and "blow the carbon out of it"

I understand the oil backing down the cylinder but why is it only when the car sits and the outside temp is cold? After the first start of the day it doesn't happen again until the next morning.

 

What I suspect may be happening is that you have a partially blocked oil galley going to the top of the cylinders. What happens is as the oil cools, it get thicker. The galleys tend to cool down first in the motor. The purpose of the galleys is to allow the oil to flow down to the pan. If one or more are restricted, they will hold oil in the top of the motor. It then starts to back down through the cylinder. It more than likely is happening all the time, but there isn't enough to really be noticeable. When you change the valve cover, look around for oil sludge around the oil galleys. You will not be able to get a good look at the valves though, you must take the head off to inspect them properly.

 

Thanks MazdaES I will have a look at the galleys. I'm still going to try the SeaFoam treatment and see if that cleans things up for me!