Puffs of blueish smoke at start up

[GeneM]

Ok, so I've noticed recently that my truck will puff some blueish smoke on startup on occasion. My truck is a 2016 1500 / 6.4l and only 66k miles on it. There is no tick noises so I don't think I'm looking at lifter/cam issues but something is certainly wrong. I've also just replaced the PCV to try and rule that out but it didn't resolve the issue, I also know I'm burning oil between my 5k mile oil changes.
Trying to figure if I have a major issue here or just a bad seal or 2 that can be resolved with some ATP AT-205 re-seal, I just dumped some in to give it a try but won't know for a while if it helps at all.

 

[Mojo88]

Bluish smoke (which indicates oil) at startup is most often valve seals, but can be other things as well. Maybe you've got some piston rings that are sticking. Or perhaps you've got some really dirty injectors that are washing down the cyl walls and causing the ring/cyl seal to break down.

Over the years, I've had really good luck with MMO (Marvel Mystery Oil). I use it regularly in my fuel, and I use it (carefully and only when necessary) mixed in engine oil. So, bottom line, I would try good fuel injector cleaner first. Then if no joy, I'd use something that would help free up piston rings. MMO should work for either application, but that's just my opinion. See what others say.............

 

[Bigskyroadglide]

If it's doing it every time valve seals, if it's doing it only after it sits a while.

Spark plug tube seals. Let oil leak down into plugs, then oil seeps past threads and blue smoke on start up.

Eventually tube fills with oil and you get a misfire, easy to check.

 

[GeneM]

If it's doing it every time valve seals, if it's doing it only after it sits a while.

Spark plug tube seals. Let oil leak down into plugs, then oil seeps past threads and blue smoke on start up.

Eventually tube fills with oil and you get a misfire, easy to check.

Not sure how oil could get past the crush washer under the spark plug, if that were happening I'd also have a loss of compression and I'd suspect it would make a vacuum noise ? That's an interesting theory, has this been something that has been an issue with the 6.4 hemi?

 

[Sherman Bird]

So far, no one has really enlightened you. different magic pookies added to the oil, improbable mechanical issue, etc.
How about this: You change the oil with a good readily available oil, not some botique, 20 dollar a quart ultra-zoot oil, just a decent type required in your owner's manual. And a factory filter for a base line.

Then DOCUMENT the actual usage/quantity/ mileage interval. Don't try to "fix" anything until you know the depth and breadth of what you are dealing with.

You could load the parts cannon, I suppose; I read about it ALL the time, AND see it here in MY shop. It's your money, after all.

Diagnosis is in order, but a base line should be established first.

 

[GeneM]

FYI, I've been running the Penzzoil Ultra Platinum Full Syn oil/Mopar oil filter for the last couple of changes and I use 7qts each time. At the 5k mark I'll dump and track how much comes out so I'll have a good idea of how much was lost/burned.

 

[Wild one]

FYI, I've been running the Penzzoil Ultra Platinum Full Syn oil/Mopar oil filter for the last couple of changes and I use 7qts each time. At the 5k mark I'll dump and track how much comes out so I'll have a good idea of how much was lost/burned.

Check your intake manifold bolts,if they're loose,the engine can suck oil past the 2 o-rings on the pcv and oil fill spout,those 2 o-rings also have a rep of turning hard,and will leak oil even when tightened down.

 

[Grams]

Valve stem seals or valve-guide issue. (I once had this same problem…no measureable oil consumption…and as unlikely as it might be….it was a cracked valve-guide. Replaced the valve guide…problem ceased.)

 

[04fxdwgi]

Valve stem seals or valve-guide issue. (I once had this same problem…no measureable oil consumption…and as unlikely as it might be….it was a cracked valve-guide. Replaced the valve guide…problem ceased.)

Yup. Puff at start up or when letting off gas (like going down a hill) and then hitting gas again and blue puff shows, it's 99.9% the seals / guides.

 

[N0NAMETOGIVE]

Not sure how oil could get past the crush washer under the spark plug, if that were happening I'd also have a loss of compression and I'd suspect it would make a vacuum noise ? That's an interesting theory, has this been something that has been an issue with the 6.4 hemi?

My 2500 6.4L has this currently, so yes it gets passed the washer. I had a random misfire which is when I found out that it was seeping through.

 

[Tominator223]

Ever change the air filter !?

 

[GeneM]

Yes I've got a new air filter and pcv..

 

[GeneM]

My 2500 6.4L has this currently, so yes it gets passed the washer. I had a random misfire which is when I found out that it was seeping through.

If you have oil getting past the crush washer then your losing compression/power.
Guess i should inspect all my plugs just to be sure.

 

[Silby]

Bluish smoke (which indicates oil) at startup is most often valve seals, but can be other things as well. Maybe you've got some piston rings that are sticking. Or perhaps you've got some really dirty injectors that are washing down the cyl walls and causing the ring/cyl seal to break down.

Over the years, I've had really good luck with MMO (Marvel Mystery Oil). I use it regularly in my fuel, and I use it (carefully and only when necessary) mixed in engine oil. So, bottom line, I would try good fuel injector cleaner first. Then if no joy, I'd use something that would help free up piston rings. MMO should work for either application, but that's just my opinion. See what others say.............

Try some ZMAX in your gas it really does some cleaning.
I also use it in my oil at every change and have done this for years.
I buy in gallon jugs, and it is the same for oil and gas.

 

[olyelr]

I have a 16’ 6.4 with 127000 miles. Had it since new. I have noticed over the years, if i would cold start my truck just to move it and shut it off, next time i cold start it, it would puff a bit of blue smoke. Never puffs any other time, either hot or cold.

Does yours puff blue smoke EVERY time you start it? Hot and cold? Any smoke while driving?

 

[jws123]

all of my 5.7 hemi trucks when parked on a hill/incline cold start always puff a bit of blue smoke never cared to figure out why run 5w30 change oil no more then 5k miles never burnt more then 1qt in between oil changes which is normal.

 

[GeneM]

I have a 16’ 6.4 with 127000 miles. Had it since new. I have noticed over the years, if i would cold start my truck just to move it and shut it off, next time i cold start it, it would puff a bit of blue smoke. Never puffs any other time, either hot or cold.

Does yours puff blue smoke EVERY time you start it? Hot and cold? Any smoke while driving?

Nope it's only occasionally and there are no clear patterns like you describe that will trigger it consistently. Mine never blows smoke while I'm driving, well not that I've noticed at least and it seems to happen hot or cold but again I'm sure I don't always catch it.

 

[AussieSRT]

all of my 5.7 hemi trucks when parked on a hill/incline cold start always puff a bit of blue smoke never cared to figure out why run 5w30 change oil no more then 5k miles never burnt more then 1qt in between oil changes which is normal.

Yes that is true, after fitting a catch can I never had any more issues