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There is no substitute.
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Discussion Starter #1
My friend was riding behind me on the highway and he noticed blue smoke coming out of my exhaust when i hit the gas... I tried revving it from it being parked and nothing came out. My brother followed me down my hill and no exhaust fumes came out but at the bottom of the hill where it goes back up i punched it and he said a big puff of blue smoke came out. :( What do you think this could be? I'm guessing the puff came after it went from 2nd or third riding down the hill to me punching it and it prolly went into 1st. I drive an auto with about 103k. Just got my oil changed about 300 mies ago or less. Car feels like its running strong with no problems and no engine light is on. any other info ide be happy to provide. plz help me out.
 

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There is no substitute.
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2,032 Posts
Discussion Starter #3
it seems like i am because i needa get my oil refilled atleast once or twice each oil change... what would a compression check cost and is burning oil even something i can fix? If i switched to royal purple or something would it burn oil less or maybe solve some of my problem?
 

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TB-3
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1,496 Posts
blue smoke = really bad
If your car is burning oil (103k is a good milage) then you might need a new motor

The blue smoke can also be a condensation problem, it happends when you don't drive the car for a few weeks

Good luck
 

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There is no substitute.
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Discussion Starter #5
hmm it rained really bad yesterday and today... and i didnt drive it from fri-mon and i ussually drive it every day. I hope these things may have affected it. As i say it seems to only do it when shifting or something, cause when im driving no smoke comes out until i punch it, and while punching it parked no smoke comes out.
 

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many words, few of wisdom
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1,214 Posts
yea my friends were riding once somewhere and we noticed some mustang with the same thing and they both commented that the guy has a cracked engine or something really bad, their dad is a mechanic so I think you got a problem there budy. maybe excess redlining?
 

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enlarged member
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417 Posts
Blue smoke is oil getting into the combustion chamber. You will see it most in between shifts when revs drop and engine vacuum levels drop because oil has a better chance to get down the valve stem.

Usually this is indicative of excessive valve wear, and the fix is a valve job (head rebuild).

Be warned, the piston rings are probably also worn, but sealing fine (otherwise you would have compression in the crankcase & oil would be blowing out of every oriface in the motor), HOWEVER, if you get the head rebuilt, and do not do the "bottom end" (the rest of the motor), the nice tight valve seal will cause the piston rings to wear more rapidly.

Solution: Rebuild time....

Note: If it is valves, you may (or should) also see some smoke when you first start the car - when it sits and valves or valve seals are worn, some oil will get in the combustion chamber and burn when you start the car.

Things to test:
!. Check the oil - you said you have to add between changes, that's a good sign its burning oil...
2. Check the sparkplugs - you will likely be able to quickly identify the cylinder(s) that are burning oil - they will be black and oily.

I would check the plugs before I shell out bucks for a compression test. The plug check will tell you if you have a problem, the compression test will tell you how severe it is.

Burning oil will also shorten the life of your oxygen sensor and the catalytic converter.
 

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Erect Member
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18,126 Posts
the following is a post that i had used on someone elses question about smoke. and btw, its easier to buy a compression checker from your local auto zone for 14 bucks than to pay about 60 to have it done. and it wouldnt be a compression check you would get done, it would be a CLT. Cylinder Leakdown Test. a CLT will accurately tell you where the leak is at. hope this helps you.


heres some helpful info.
and this is different from a diesel.
white=water or coolant.
blue=oil
black/grey=fuel (unburnt or rich)

symptoms for each are:
blue=rings(smoke all the time)
blue=valve seals(smoke inbetween shifts and first start of the day)
white=head gasket or cracked water galleys
black=bad o2 sensor (actually too many to list for black but its almost always a fuel problem)

easy way to tell if its oil or fuel is to stick your finger in the tail pipe and smell the residue. fuel will have a nasty exhaust smell with a strong fuel background smell. burnt oil just stinks. also if its fuel, it will mostly be flaky and grainy, whereas if its raw fuel it will be wet which could be an indication of an injector or injector seal going bad. oil will just smudge your fingers.
 
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