Blue Smoke on cold starts??

[DuckLN]

Three or four times this fall I've noticed a small amount on blue smoke on start up on some colder mornings (38-50 F) so I checked my PCV valve yesterday and it has the click when you shake it so I assume its working. Smoke clears after 4 or 5 seconds and there are no other symptoms.

I also checked the oil and it is perfect.


Are there any other underlying issues that may cause this? (I'm hoping (like Barack) this is not valve guides or similar engine issues)

Thanks

 

[OregonLC]

How many miles?

The 2uz-fe does have a known piston slap condition at cold temps. I would thing the rings would continue to seal though. Sounds like you're not seeing any oil consumption between changes? If so I probably wouldn't worry too much.

 

[DuckLN]

Got 158,500 on the clock.

I dont have the cold knock others describe.

 

[2000UZJ]

Running rich? I had blue smoke after a the exhaust install...however it only lasted about a day. Blue smoke usually means it's burning oil due to internal parts wearing. Do you use additives? Stabilizers? What type of oil? Do you drive it hard?

 

[DuckLN]

Always babied and I mean babied. Changed oil with Castrol GTX every 3-4k miles. Old oil has never appeared "solid black" and always still looks clean. I've never added an additive.

Scary stuff.

No CELs or any other symptoms.

 

[hkeller]

Possibly valve guide wear. Our 2000 started this with about 130K on the clock. Funny thing is, it is not consistent. If it is valve guides, I would think it would smoke at every cold or overnight start, but it doesn't.

 

[gtfour43]

Always babied and I mean babied. Changed oil with Castrol GTX every 3-4k miles. Old oil has never appeared "solid black" and always still looks clean. I've never added an additive.

Scary stuff.

No CELs or any other symptoms.

What viscosity are you using?

 

[e9999]

how much are you using between changes?
if it's a tiny amount, no need to panic

 

[2000UZJ]

It could also be a build up of carbon deposits. If you "baby" your truck, you may not be blowing out all the unburnt garbage. It's actually good to run through all your gears and top out in each gear every now and then to "clear" the system, if you will. We have a A4 in North Carolina and my mother drives it when she flies over, she drives like a grandma, and after a while it started to emit smoke. I got on it a few times and left some black/blue soot after I shifted and ran through the gears pretty hard for a few miles after she warmed up. It took care of the smoke, so I do it in all the family cars every month. If your engine is infact burning oil, I think you are the first 100 owner to have internal seals, etc go bad. Blue smoke is generally from burning oil (or carbon/sludge build up, but generally that is a dark color). I would go out for a drive and do a couple on-ramp pulls and slowly build up the revs and take note of the smoke/running condition. If you do decide to do this, please remember my suggestions are based on experience and a bit of research on engines, so when your piston goes through your hood, please don't be pissed at me

 

[Bismarck]

Possibly valve guide wear. Our 2000 started this with about 130K on the clock. Funny thing is, it is not consistent. If it is valve guides, I would think it would smoke at every cold or overnight start, but it doesn't.

Shouldn't the valve guides make a noticeable racket at startup of they're going out?

 

[GaFJC]

Possibly valve guide wear. Our 2000 started this with about 130K on the clock. Funny thing is, it is not consistent. If it is valve guides, I would think it would smoke at every cold or overnight start, but it doesn't.

Mine does the same occasionally but doesn't burn oil between changes. I wouldn't worry about it. I have 132k on the odometer.