For a while now I've noticed a white/blue smoke when I start up my truck. I guess its more white than blue and it typically happens when the truck has been sitting a few days. It had been sitting since Sunday (four days) and when I started it today it smoked at start up and for 10-20 seconds after.

Y'all think this something to worry about or just condensation build up in the exhaust system.

Thanks

 

Could be a couple of things, none of which in my opinion are really anything to worry about. But this is just my guess based on what you wrote.

- Condensation. Likely source for white-ish steam coming out of the tailpipe. If it evaporates after leaving the pipe (unless it's really humid outside) then that's likely it.

- A bit of oil from the PCV could be settling on the valves, then getting burned right at startup. That would cause blue smoke. Not a big deal if that's the source of the blue smoke.

A little more on PCV...

Every vehicle has some sort of PCV system. It's needed as a means to release air pressure in the oiling system to keep from blowing oil seals. Environmental rules don't allow that to be vented to the open air. So manufacturers typically use a PVC valve (a one-way pressure release valve) that generally sits on the valve cover or somewhere on the cylinder head. From there is a tube that leads to the air intake. So effectively, the PVC air (that has oily vapor in it) is being put into the air intake. At normal operating temps, the oil is a vapor. Let it sit a while though when the engine cools, and it'll turn into small drops of oil, which will then trickle down to the lowest spot they can find. On startup, that oil is either sitting on the valves, or some other low spot in the intake, and it'll get sucked into the engine. There's your blue smoke on startup.

It's generally not a big deal. Some people (like myself) are a little OCD about stuff like that. I've ordered a PCV filter that I'll install once I pick up my truck. All it does is catch most of the oil vapors and lets it puddle up in a container rather than in the intake or on the valves. No real need to do so...people drive for hundreds of thousands of miles with no issues. But like I said, I'm a little OCD about stuff like that, and I'd rather not have oil getting into my air intake and possibly gunking stuff up over time.

 

Could be bad valve stem seals. Using thin oil like we use it can seep by the seals.

 

My guess is that you only have a few thousand miles on your engine. If so, it will go away after your engine breaks in and the rings seat. Same thing happened to mine and quit but I forgot when. I replied to this same topic a while back and I think it had stopped around 10k but I'm not sure. It hasn't done it since and I have 19k+ on it now so I wouldn't worry about it. The rings take a while to seat in these 5.7's which is a good thing so you are fine. I'll go check my old post to see exactly when it stopped and get right back on this. EDIT:I went back and checked...I never knew when it actually stopped but had noticed that around 10k miles it wasn't doing it any more. So...and according to Chrysler, if you have low miles on your truck that's more likely what it's from.

 

I've had that happen a couple times, at widely placed mileage.
I think the thin oil has a lot to do with it. I asked the dealer. They had no idea. As usual. I can only imagine it is oil leak down. Not BAD seals just leak down. At start up it may start off a bit rich and washing down the cylinders as well. Mine only does it a few seconds. If it did it longer than that I'd get worried. Of course it has only done that twice. Both times after sitting for a few days. Another thing both times my truck was parked on an angle. I have a steep driveway. Don't know if that has anything to do with it. Next time I leave it for a length of time I am going to park it on a flat section and see what goes...

 

Thanks for the feedback. I'm feeling a lot better about this now. I have about 20K on the truck but it does sit for a week at a time sometimes.

I know this will start a debate, but any thoughts on my switching to full syn oil after the first oil change having any impact? I think my first oil change was at 5K.

Thanks again!

 

No because I have had two oil changes in between my blue smoke shows and I still am running regular oil.

 

I like debates, it's just peeps opinions anyway, lol! I used the synthetic for my second oil change but haven't since. That's when I heard my first engine ticking coming from my valve train so I took no chances and switched back. However, I don't think it would have mattered either way because I found out it had nothing to do with what oil I used. But if I were you, I would try the synthetic just to find out from your own personal experience instead of opinions alone...it wouldn't hurt and you can always switch back. I'd like to share a little tip about our engines....that is if you got a Hemi anyway, lol! We have 10.25 to 1 CR, in our trucks which has a lot to do with soot in your tail pipes and maybe some blue smoke at times. I know they say we can run 89 octane fuel but I don't think we should, at least as little as possible. If we didn't have dual plugs and quench pads we would surely have to run premium gas. Quench pads are the small flat areas on two sides of the chamber and are there to keep the fuel closer to the center of the pistons nearer the valves and spark plugs, creating less volume sort of speak. This helps to assure the combustion and prevent any raw fuel from escaping out the exhaust...something new I learned about these engines (qpads). If any raw fuel does exist...it could cause some minor smoke and it could also cause a oily looking carbon build up in your tail pipes. FACT: Raw fuel (it doesn't take much) can be an engines worst nightmare. Bottom line is, use PREMIUM gas to eliminate any possibilities that may be causing your smoke, lol! At least try it all through your next oil change, you just might be surprised. Incidentally, the old Hemi never had quench pads and unspent fuel was a big issue with high volume large chambered heads so these pads make a lot of sense to me. You guys out there that are set on running 89 octane...good luck and more power to ya, he he!

 

I get the blue smoke occasionally on startup, usually if its hot and sits an hour or so or it sits a few days unused. If I didnt have remote start I would never notice it, I have 13K miles on it, non synth oil. It uses no oil between changes (4-5K between changes) so I'm not really that concerned about it. Besides it has 87,000 more miles to go under warranty