Occasional blue smoke upon start up w/ 5.7L?

Anyone else have occasional blue puff of smoke at start up? I recently bought a used 2007 Crewmax with the 5.7L. It has 109,XXX miles on the truck. I noticed a day or two after I bought the truck that it would occasionally(2 out of 5 times?) puff a small cloud of blue smoke out upon start up. I did a little bit of reading on some online forums and immediately ordered a new PCV valve. I installed that over the weekend hoping it would take care of the smoke issue, but it hasn't. Do these 5.7L motors smoke a little after they have some mileage on them? I've checked the oil level and its good. Anyone else have a puff of blue smoke on start up?

 

Blue smoke isn't a healthy engine, signs of bad piston rings and oil is mixing with fuel during combustion. I've got 200K miles on mine and it doesn't smoke at all, only white condensation smoke that goes away after a couple minutes.

 

Doesn't the 5.7 run rich to begin with and could this be a factor in the smoke?

 

Running rich would be black smoke. Blue smoke is oil. Blue smoke on startup is usually valve stem seals.

 

If it’s just on start up, valve seals maybe?

 

Not sure if this helps but we had a 2006 Jeep with a 5.7 Hemi in it and it started to do the same thing your describing. A small puff of blue smoke only at start up and never again. Also it needed to sit a while like over night and it would reoccur. Turned out to be a loose spark plug. Synthetic oil will find the smallest gap. Just a thought, It went away after checking all plugs.

 

I will check the spark plugs this weekend. That would be awesome if its that easy.

 

Also, do a SeaFoam treatment to help get rid of any deposits in the engine. You might just have dirty valve heads and they are not seating properly. Be sure to change your fuel filter after. Also run a high quality fuel at all times to keep it clean.

 

Did you ever figure out what was causing this? I am currently having the same issue with a 2014 Tundra 5.7L

 

Could it be condensation? From the prior start? On major temp swing days, after I get to work, then start later, there is a bunch of condensation/steam.

 

I always get the condensation but it dissipates almost immediately. This a blue puff of smoke, out of the tail pipe right at the moment of start up. I am thinking valve seals, bad piston rings etc...? Toyota mechanics have not been able to figure it out either, very frustrated...

 

As stated earlier, this is often due to leaky valve stem seals. It lets a small amount of oil drip into the combustion chamber and is immediately burned off on startup. It often requires the vehicle to sit for some time (overnight) for the puff of smoke to happen again.

 

Got it...sounds like something I have time to fix then, but obviously not to ignore it! Thanks

 

Yeah it will get worse over time, but will probably happen very slowly.

 

Most of that dates back to vehicle maintenance and use. Good oil, with OCI on time for the conditions and not starting it and running the p$ss out of when cold.

The question you need to track is how much oil is being used. A puff is nbd. Descending a long hill while engine braking tests the valve stem seals as intake manifold vacuum is at max. Look in the mirror as the throttle is applied. If no blue smoke, it's very likely the seals are okay.

Monitor oil usage between OCI. If all is well, keep good oil in it and carry on.

If consumption is positive, try a couple treatments of Yamaha Ring Free just before your OCI is due. Run the treatment and change the oil.

GL

 

Intermittently, and with no regularity, my 07, 5.7L with 79K will puff a little blue smoke on startup. This started at about 75K a couple of years ago. Zero oil consumption. Sometimes the truck sits overnight and sometimes for weeks at a time between starts. As much as I kept looking for a pattern, there was none. Now I just don't worry about it. (My John Deere does the same thing????) IF, the occasional blue smoke start up is symptom of a pending problem, WHEN it affects either performance or reliability, I'll just get it fixed.

 

Start changing the oil every 5000 miles if you are not. The rings are gumming up.

 

If it's not using oil, I wouldn't worry about it either.

As I said above, dropping gears down long grade for engine braking look in the mirror when you first apply the throttle again. Is there blue smoke? The intake manifold vacuum will be at max which strains the intakes valve stem seals, any oil pulled through shows as a blue ploom when the throttle is opened.

 

Nope, none, zip, nada.....Was one of the first things I did after first noticing "blue smoke". Oil and filter is changed once a years (driven less than 3K per year). Puzzleing, but, as I said, could go on like that for years......

 

I feel, It's the low tension piston rings. Once they start to gum up it will start to smoke on start up. Mine started doing this when I was only doing 10000 mile OCI's and once a year. I increased the OCI 5000 miles or 6 months, occasionally drove it like I stole it, and it went away.

Is this for sure what is going on with yours? No, but just passing on my experience when it was happening to me. Those low tension rings can easily gum up.

Also I think these trucks need to be ran hard from time to time, especially if they are driven very little. YMMV

 

Yep, I agree. My Tundra is used almost exclusively for towing - occasional RV, but mostly a horse trailer, spring thru fall, to rodeo's. When it's driven, it's driven hard.

 

Thanks, i will try the yamaha ring free. looks like a good product with positive reviews. oil consumption test came back with no issues.

 

thanks, already doing that.

 

Someone mentioned loose spark plug causing blue smoke ... I don't see how but may be it's above my pay grade.

Can someone explain?

 

Coked rings, just like in the Camry. Toyota has been having issues with the 5.7. 3URFE and the aformentioned 2.4 2AZFE Been a problem for a long time.

 

Yep. An this is why most vehicles fall under the 5000 mile OCI.

 

I noticed blue smoke at startup as well - 2010 5.7 with 150K miles. I pulled the PCV to check it and it had failed. Since replacing the PCV I've not had this happen again.

 

The early 2GR-FSE (Lexus IS-350) had low tension compression and oil scrapper rings 2006 - 2008 and later changed the piston design to facilitate new rings and oil scrapper to mitigate oil consumption.

Just saying they went through a learning curve while aiming for higher fuel efficiency engines.

 

ADD a oil catch can to your PCV valve, I did and it’s catching a lot of milky coffee oily stuff in there you don’t want in your inlet !

 

I’ve had this happen twice now. 2018 with 38k miles.