I'm a little stuck.

So I have an 08' 2.7l 153,000miles 5spd.
I've been worried my truck has been burning oil or coolant. All fluids look/looked fine no chocolate milk, coolant and oil levels have never been low as far as I'm aware.
I just had a pressure test done on the cooling system, I chose that over a leak down test because the smoke coming from the tailpipe appears white. I just got the results and the system held pressure perfectly for 30 mins. Why is my tailpipe smoking on startup only??? I'm so lost now. The smoke has a smell, a little sweet and is white.

 

WAG. The leak closes when the system heats up.

 

It is probably burning off the condensation accumulated in your exhaust system. You will see more of that if you are in an area with a high dew point and if you park outside.
Sweet smell and white smoke would indicate coolant. You might pull some plugs and inspect the color. You could have a cracked head, although a cracked head usually produces quite a bit of smoke.

 

What does WAG mean? Are you saying, if coolant is getting into the combustion chamber, it closes when it heats up? If so, why is my coolant level the same? How does that work? Is there a concern?

 

There is quite a bit of smoke on startup, yes I do park outside, I am in northern New England. But when the smoke first starts to come out of the exhaust on startup it does smell.when I put my hand up to it first thing, the smoke is cool, and smells and after 2 or so minutes I put my hand up again and my hand becomes wet and it smells like water.

 

Also the mechanic used his scan tool on the trucks computer and said that also came back perfect. IDK what he was looking but .

 

This was my initial thought as well. OP is the truck new to you or is what’s going on with your truck now new to you?

 

Wild Ass Guess (WAG)

 

Are you saying a big white puff of smoke the is gone? Or smoke like on a cold morning because difference of exhaust temp to air temp?

 

So ive had it for a few months. I've been chasing rust and gaskets and brakes and etc. there was one day, not cold that I started the truck and a HEEPING amount of smoke came out of the tailpipe and since then Ive been trying to figure out what it is. I flushed the cooling system(has never overheated) I changed the oil twice in the few months I've owned it out of fear of burning oil and I didn't mark the dipstick the first time I replaced it. I don't drive much 1-2 times a week. I park outside. I'm in New England. I understand it COULD be condensation but when I start the truck first thing there's a good amount of smoke that comes out. It's white, and it smells what I THINK is coolant. (Don't know the difference in smell) And it's cold when it first comes out then after ,2' minutes when the rpms drop a little bit what I know is condensation comes out. It's warmer, it wets my hand and it smells like water. So I'm trying to figure out why my truck is smoking on first startup.

 

My gut says if its right at start up it could be possible valve guide seals.

 

It's almost winter and there's condensation?

One of the primary byproducts of burnt gasoline is water. A tailpipe will always be humid, and seeing a water drip is normal. Abnormal white smoke will be when the dew point is significantly higher than current temperature or that its persistent after the engine has warmed.

If its coolant, its going to smell sugary.

 

It’s definitely worth looking into, I just can speak from personal experience that when I get new things I’m usually a little overly concerned about little things that are actually normal

 

A short video of the smoke might help folks figure this out.

 

Did the heaping amount of smoke come out on just that one startup, or does it do it every time you start it after it sits for a while?
If it was just the one time, if you started it the day or night before and only let it run for a few seconds, like to move it, and you shut it off while it was still on high idle, you can load the cylinders a bit with unspent fuel and it will smoke/stumble a little the next time you start it.

 

It takes about 15-20 for the tailpipe to start smoking.

I don't remember exactly if I ran it for a minute or took a drive. But it was that one time that ALOT of smoke came out. After that id say it's a concerning amount but maybe about half the amount comes out now.

 

I've been trying to upload a video but it won't let me.... Here's two screenshots from the video

 

Wow that's a lot of smoke.

 

That is, thanks for posting the pictures, it sure looks like something going on with your truck

 

(WAG) Wild Ass Guess
(SWAG) Scientific Wild Ass Guess. A more educated guess.

Under certain conditions you'll get water condensation (steam) at start-up and it will continue for a few minutes. Any vehicle even new will do this.

As trucks age and get some miles on them a little oil will seep past the cylinders and burn at start-up. If it's only for a second or 2 and the truck isn't using excessive oil it isn't anything to worry about yet. It's just a sign your truck is getting old. It could do this for years and another 100,000 miles before it gets bad enough to be a problem. If you're puffing smoke while driving down the road your engine is almost gone.

My 07 has 251,000 miles on it and does this occasionally and has been doing so for a few years. Only after being parked for 4-5 days and not driven. I still don't have to add any oil between oil changes, and I'm not concerned in the least. When I start adding oil every 2000 miles it's time to start coming up with a plan. A quart of oil less than every 1000 miles then it's time to do something.