White smoke coming out of exhaust

[werepossum]

I thought it meant we had a new Pope.


heyooooooo. Mmthenkyouthenkyou.

don't know, but before i started experiencing the problem, i had just put gas in the car, so maybe when i was driving home the trans fluid kicked in?!....dont know. but something is burning at the bottom of the engine and i can't figure out what it is. i don't have any tools to check the spark plug.

Have you tried a good water remover gas additive? If this started just after adding gas and the engine is otherwise running normal or maybe even a bit better than normal, you may have a tank of gas with enough water to produce white smoke but bonded with the ethyl alcohol in the gas. Those of us who experimented with water injection to boost horsepower back in the day can attest that a very little bit of water can produce visible white smoke.

Another thing to look at is your tailpipe itself. If you have broken rings, you should be burning enough oil to have black grease (oil residue) inside the tailpipe. This is also a condition which typically progresses fairly quickly into producing a LOT of smoke - and will quickly damage the cylinder wall as well, so that your engine has to be bored out or sleeved to be rebuilt. If you're looking at coolant being siphoned into your cylinders on the down stroke (classic case for white exhaust smoke, usually because of a blown head gasket) then the grease will be thin, little worse than that found inside the pipe of a car similar in type and miles. Oil smoke typically does not fully burn, so the excess accumulates in the pipe.

EDIT: Forgot to add but broken rings are easily detectable via a compression test, something any competent shop can do. Obviously all your rings aren't going to fail at once, so one cylinder should have noticeably less compression (thus allowing more oil to slip through than is normally burned.) A good mechanic can often diagnose low compression on a high end Sun machine or similar as well; since that cylinder produces less power, there is a micro-stutter in the engine's pace. Coupled with monitoring the plug wires, the machine correlates this micro drop in rpm as a cylinder producing less power than its brethren.

With smoke coming out of the engine compartment, might also look at an intake/exhaust manifold vacuum line leak, one that is sucking extra oil into the intake and also blowing/leaking oil onto the exhaust manifold. Seems odd to have white smoke suddenly coming from both, and oil smoke from a very small leak into the intake via vacuum lines (from a malfunctioning valve) or directly into the cylinder can look pretty white.

I'd have thought an '06 would be throwing a trouble code if it's noticeably smoking. And seriously, dude, a decent spark plug socket with a cheap torsion bar torque wrench (I'm assuming your head is aluminum) and extension are pretty cheap. That and a code reader should be the absolute minimum diagnostic equipment to avoid getting ripped off unless you have a friend or family member who is a mechanic. Surely you know someone able and willing to pull the plugs* for examination? If not, maybe widen your circle?

(*With the unspoken "and savvy enough not to strip the threads in the process.")

 

[dawp]

Years ago I had a modulator valve go out on a ford I was driving at the time, it was sucking trans fluid directly into the the intake and producing vasts amounts of white smoke.

you might want to check the fluid levels in your transmission.

 

[sontakke]

wait until you start losing some fluid and/or there are other symptoms. since you have no tools, it probably is not productive to offer you other suggestions. you can obviously get a second opinion.

 

[VRTrooper]

HI everyone, seems the previous shop i went too was deceptive. the new shop says that the valve seals were a bit worn, but my engine was overfilled with oil, by two quarts, causing overflow and it burning. They also told me that i had a crack in my exhaust system, causing the car to drive and sound rough( I never noticed tho, but my aunt has, so it explains her complaints). I also was told that my O2 sensors weren't working. The guy also said there was nothing wrong with my pistons rings and there aren't any leaks in the car.
He gave me two options:

fix the valve seals for 1300-1400 dollars or do an oil change to eliminate the overflow. He'll add some high mileage oil in it(it has 126k miles) and some additive( i forgot what it was, but he says I can't get it over the counter)
fixing the crack is approx. 195 and replacing the O2 sensors is 225. Decided to take the minimum hit to the wallet.

but does 1300 to 1400 sound right for fixing the valve seals??

 

[MiataNC]

Get a second opinion.

1. The ONLY thing you need to do right away is get the oil level right. You do NOT need a complete oil change if the oil was changed recently. All they have to do is pull the drain plug and drain a couple quarts, or vacuum a couple quarts out.

Don't waste money on seals until you have put some miles on the car with the oil level right. The smoke may clear up, and your valve stem seals could be fine.

2. O2 sensors will trigger an check engine light if they are operating out of spec. If you don't have a check engine light, and the car performs normally, the O2 sensors are fine.

3. What part are they replacing to fix a "crack" in the exhaust? - $195 is pretty cheap for replacing a component in the exhaust system. They may be fixing something a lot cheaper and gouging you.

 

[VRTrooper]

Get a second opinion.

1. The ONLY thing you need to do right away is get the oil level right. You do NOT need a complete oil change if the oil was changed recently. All they have to do is pull the drain plug and drain a couple quarts, or vacuum a couple quarts out.

Don't waste money on seals until you have put some miles on the car with the oil level right. The smoke may clear up, and your valve stem seals could be fine.

2. O2 sensors will trigger an check engine light if they are operating out of spec. If you don't have a check engine light, and the car performs normally, the O2 sensors are fine.

3. What part are they replacing to fix a "crack" in the exhaust? - $195 is pretty cheap for replacing a component in the exhaust system. They may be fixing something a lot cheaper and gouging you.

the check engine light has been on since i bought the car last year. and i never did an oil change since i bought the car, so it looks like one was needed anyway.


I don't know what the exact part was that had a crack on it, but it causing the car to idle rough or sound rough. and this shop is my second opinion, the first shop said i had bad piston rings and to replace was 1200 to 1300(they didn't even tell em about the other problems, like O2 sensor and the crack). the current shop says i don't have a piston ring problem and there no leaks in the systems, besides the oil overflow.

 

[pauldun170]

the check engine light has been on since i bought the car last year. and i never did an oil change since i bought the car, so it looks like one was needed anyway.


I don't know what the exact part was that had a crack on it, but it causing the car to idle rough or sound rough. and this shop is my second opinion, the first shop said i had bad piston rings and to replace was 1200 to 1300(they didn't even tell em about the other problems, like O2 sensor and the crack). the current shop says i don't have a piston ring problem and there no leaks in the systems, besides the oil overflow.

Crack in the exhaust? You mean "Exhaust leak".
120-150 sounds like a simple exhaust repair. You can figure out where the leak is by getting under the car and using your ears.
A leak after the cat shouldn't cause idle issues. A leak ahead of the car, in the cat or north of any of the 02 sensors will cause a rough idle.

Driving around with the check engine light is a stupid thing to do. The only valid excuse is "I'm broke".

White smoke - Coolant leaking into the combustion chamber. Drop the oil and look for coolant. Drop the coolant and look for oil.
Cracked head, blown seals would explain both the white smoke and the "extra oil".
If you can't find it then you need a pressure test

 

[VRTrooper]

Crack in the exhaust? You mean "Exhaust leak".
120-150 sounds like a simple exhaust repair. You can figure out where the leak is by getting under the car and using your ears.
A leak after the cat shouldn't cause idle issues. A leak ahead of the car, in the cat or north of any of the 02 sensors will cause a rough idle.

Driving around with the check engine light is a stupid thing to do. The only valid excuse is "I'm broke".

White smoke - Coolant leaking into the combustion chamber. Drop the oil and look for coolant. Drop the coolant and look for oil.
Cracked head, blown seals would explain both the white smoke and the "extra oil".
If you can't find it then you need a pressure test

I've been through this, the guy has not found any leaks in the system, they did a pressure test right in front me..nada. even before that i did all the tests myself, no chocolate milk color or oil in the coolant. he said that I have a Valve seal/seam/sleeve issue and it was worn, but oil was over flowing since it was overfilled by two quarts causing the oil to overflow and burning smoke behind the engine and out the exhaust. I don't have the cash to do a 1300-1400 dollar job to fix those valve seals/seams.

 

[pauldun170]

I've been through this, the guy has not found any leaks in the system, they did a pressure test right in front me..nada. even before that i did all the tests myself, no chocolate milk color or oil in the coolant. he said that I have a Valve seal/seam/sleeve issue and it was worn, but oil was over flowing since it was overfilled by two quarts causing the oil to overflow and burning smoke behind the engine and out the exhaust. I don't have the cash to do a 1300-1400 dollar job to fix those valve seals/seams.

Did YOU drain your oil into a pan and inspect the oil? Coolant stands out in the pan.
Did YOU drain and inspect your coolant?

At the very least you should be under you car right now, draining your oil to take care of the over filled condition. Check the oil in the pan. Might as well do an oil change and make sure you put the correct amount in.

For 2006 Sentra with those miles, I wouldn't bother pay someone to fix valve seals at this point. I half expect you to post on here in a few months about a catalytic converter issue.

 

[VRTrooper]

Did YOU drain your oil into a pan and inspect the oil? Coolant stands out in the pan.
Did YOU drain and inspect your coolant?

At the very least you should be under you car right now, draining your oil to take care of the over filled condition. Check the oil in the pan. Might as well do an oil change and make sure you put the correct amount in.

For 2006 Sentra with those miles, I wouldn't bother pay someone to fix valve seals at this point. I half expect you to post on here in a few months about a catalytic converter issue.

why so negative? and what makes you say that?

 

[LTC8K6]

I've been through this, the guy has not found any leaks in the system, they did a pressure test right in front me..nada. even before that i did all the tests myself, no chocolate milk color or oil in the coolant. he said that I have a Valve seal/seam/sleeve issue and it was worn, but oil was over flowing since it was overfilled by two quarts causing the oil to overflow and burning smoke behind the engine and out the exhaust. I don't have the cash to do a 1300-1400 dollar job to fix those valve seals/seams.

The drain and refill amount on that engine is only 2-7/8 quarts...

I don't think you can get 4-7/8 quarts in there...

And if you did, I think it would be spectacular...

 

[pauldun170]

why so negative? and what makes you say that?

I'm not being negative.
I'm asking you if you personally inspected the oil in the drain pan.

I mentioned the catalytic converter because cat failure on Sentra's is fairly common around here, especially those neglected by owners.

 

[MagickMan]

blown head gasket

 

[monkeydelmagico]

Overfilled by 2 qts on that tiny motor? Damn.... you ever pull the dipstick and check your levels? Should be doing it monthly on an older motor. Easy to verify if the 2nd shop is B.S.ing.

If indeed it is overfilled then just get the oil level right. That will solve alot of your issues like smoking and O2 sensor fouling.