2021 3.5L White or Blue smoke on ignition???

Hey All - the classic white or blue cloud of smoke when starting my truck has happened. Can’t tell the color exactly. Only happens after it sits for a few hours after driving. 80k miles.

Guides and valve stem seals? Head Gasket? Coolant level good, oil level good, no engine lights. Doesn’t seem compression related and no strange noises. It’s summer by the way, not cold out.

Any recommendations on how I can go about diagnosing this issue? Any one have experience with this issue and your outcome?

Please let me know!

 

I know this is going to sound like a funny question, but what does the smoke smell like?

 

Normal exhaust. Doesnt really have too strong of a smell unless I get my face in the thick stuff lol I’ll report back if I smell anything sweet or burnt

 

Are you the original owner? Is engine oil turning white, chocolate color? Check coolant level, in radiator itself, when engine cold?
Tacoma was it ever serviced, sparkplugs replaced? Probraly time to replace sparkplugs if not, at 80k miles.

 

Is a code reader showing any codes?

 

I would proceed to troubleshooting a cylinder head gasket leak. FTW. Keep reading.

1) Modern cylinder head gasket leaks can be so small, like pinhole sized, that they don't affect ordinary driveability. Except for perhaps symptoms such as smoke or vapor upon a cold restart as you are describing.

2) That you are not losing noticeable coolant supports my theory. We are talking teaspoons of coolant leakage - at most per drive cycle. In some drive cycles, the cylinder head gasket gets hot enough while driving that it acts as if it has re-sealed itself. And coolant is not actually being lost while driving.

3) What happens with a pinhole cylinder head gasket leak is that, upon a hot engine shut down, and a still-pressurized coolant system, is that coolant starts to dribble into the cylinders. As the cylinder head gasket cools and shrinks to the point the pinhole manifests itselft again. And that 20-25 psi of coolant system trapped pressure is looking for the proverbial path of least resistance.

Presto. Although humans have tried countless times, nobody has been able to defeat Sir Isaac Newton's laws of physics.

I'm talking droplets at a time. Over the cool down period. Drip. Drip. Drip. With either an intake or exhaust valve partially open to atmopshere. Until the coolant systems leaks down to 0 psi and the dribble dripping stops.

Meanwhile, you have accumulated a very very small puddle of coolant on top of your piston(s). I'm talking a teaspoon. Maybe 1 cc. Or less. That does not evaporate easily. But it is not enough, in fact nowhere near enough, to hydrolock your engine. What happens is that tee tiny puddle pretty quickly, like within seconds, gets heated by combustion temps on a cold re-start and is spit out the exhaust. As white / blue smoke. That goes away.

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This can be a very difficult diagnosis to confirm. Make no mistake about it.

* Coolant "block test kits" can be misleading and give you a false negative the leak is so small.

* Ditto pressure testing your coolant system - which should hold ~25 psi 'bubble tight' for about the same number of minutes. Rule of thumb. However, the cylinder head gasket leak can be so small that it can be difficult to discern thermal fluid contraction as the coolant cools down in contrast to an actual leak.

* Often times, the only way to conclusively prove this is to wait until you start get misfire counts in your PCM. You may already have misfire counts being stored, but they may not be enough yet to trigger a Check Engine Light and throw a DTC (diagnostic trouble code). Plug in a scan tool and check!

* Pull your spark plugs. And run a boroscope camera. If you can do this while the engine is still hot (not likely), you will see the coolant fluid dripping. If not, you should see the spots where the coolant is "steam cleaning" your piston and cylinder wall and that alone can be the diagnosis.

I WOULD MUCH RATHER YOU CONTINUE TO DRIVE YOUR TRUCK, WHILE CLOSELY MONITORING YOUR SITUATION THAN JUST RANDOMLY GUESSING AND START REPLACING PARTS.

This drives me bat chit crazy when people spend hundreds and even thousands of dollars just guessing and replacing parts to no avail. And then re-post "What could still be wrong?" Don't be that person, please.

This is going to be a challenge.

If this were my truck, I would be OK continuing to drive it, gently - but normally. But I would also have an OBD-II scan tool plugged in at all times to be checking on real time engine PIDs.

 

I appreciate the reply! This helps my confidence - I haven’t needed my OBD in so long I gotta dig it out LOL. Since I drive a lot for my job and bow hunting season around the corner - I may just turn this bad boy in for another while the problem is so small.

 

I think it indicates if a new pope has been elected

 

It will inevitably get worse and develop a miss/skip at idle but run fine at normal running rpm. It's happened to me on another vehicle that I just kept driving

 

what ended up happening with that situation?

 

^ this is really funny ^
Cardinal Citron has been elected Pope of TacomaWorld.
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If you have not yet watched the movie called "CONCLAVE", I highly recommend it. No matter your faith.

The cinematography alone is enough reason to watch it. Like if that is even "close" to what actually happens - it boggled my mind.

The plot and plot twist at the end are also superb.

 

Well sounds like you either need to trade or fix it. Ultimately that is your choice. Good luck

 

I got $2300 in trade in with 246k miles on the vehicle and it was overheating on the way to the dealership. Long story short I had a shop do the radiator install at 200k miles and the overflow port in the radiator was blocked off with plastic when it was installed (manufacturer defect). This probably caused the issue in the first place.

 

CYA problem for the shop that replaced radiator ar 200k miles. They did not check that overflow port in radiator, was blocked off?

 

FYI - what will usually happen with a pinhead (pinhole) sized cylinder head gasket leak is that - yes, indeed - it will eventually get worse. It may take weeks or even months, but it will happen.

Leaks never resolve themselves. And "stop-leak" products never work. So don't even think about using them. In simple terms, and I greatly exagerate here, it is like adding liquid sawdust to your coolant (or oiling) system. No bueno.

Anyway, eventually, the coolant leaking into the cylinders will become significant enough that misfires will start occurring and throw a CEL. At some point thereafter, one will also start to experience mild overheating and coolant loss symptoms.

That becomes your Go / No Go point for continued operation. And where a confirmation diagnosis and repair really should be performed. ------
Should this peliminary diagnosis be correct, it is an absolute shame you only got 80k miles and ~4 years outta your head gasket. I would be bummed. I don't recall where I saw this or read this. And it may not have been a Toyota manufacturer issue. I was probably watching South_Main_Auto or Pine_Hollow_Diagnostics on YouTube. Or a similar channel.

Customer had a head gasket leak. And it was known the manufacturer had an issue. Their vendor supplied multi-layer head gaskets that were used in engines over a certain build period were delaminating and causing pinhole leaks. I don't recall it being a warranty issue as mandated by the gubmint. But you may wish to check the TSB (technical service bulletins) that are published for your year and model Taco.

A TSB is an industry wide methodolgy for dealerships to more easily ID and repair commonly occuring failure issues - that are *not* safety related. Its been a while since I've looked one up, but TSBs are required to be published for public availability, reference and self-use. You might check and you *might* at least get a break in terms of a dealership repair.

IIRC, I think the infamous 3rd gen cab mounted stop lamp rainwater leak into the rear of the cabin was a TSB issue. Ironically, and coincendentally a gasket issue.