blue exhaust [Archive] - Forum


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10-01-2007, 05:52 PM
i know blue smoke from the exhaust is a tell tale sign of burning oil.. but my question is does it ALWAYS 100% mean burning oil? i let the finance borrow my car and as she pulled away i saw what usually pours out of her saturn...

i guess the next question is, what could be causing the oil to burn?

:blushing: i did something that i probably shouldn't have last time i changed the oil. i bought my oil (Castrol High Milage 5w30) from advanced auto parts and it was a damn gallon jug instead of 5 quart.. so i was about a quart low... so then i came across an real old quart of regular Penzoil 10w30 and i put that in :nono: could blue smoke be a result of mixing oil, or using a old oil (the bottle was covered in dust and was not the current labeling on Penzoil....)? (i know... why?? :banghead not sure why.. wasn't thinking clear..)

10-01-2007, 06:02 PM
I would say start over with a fresh oil change with all the same oil, and if it keeps burning blue after ~300 miles you might want to consider other causes.

10-01-2007, 06:29 PM
I would also suggest if you're getting still a little blue after the oil change, running some seafoam in the oil for awhile before the change to clear out any bad deposits.

10-01-2007, 06:33 PM
piston rings could be shot

10-01-2007, 07:11 PM
Or bad valve guides...

10-01-2007, 07:25 PM
Could mean quite a few things actually. A leak somewhere even? How would he start to narrow it down?

10-01-2007, 07:43 PM
pressure test to the pistons, A shop has a tool that goes into the spark plug hole.

10-01-2007, 08:03 PM
my brother needed some oil and his girl friends dad put in some old oil from her ford taurus( oil change) :confused: he should have called me i would have brought him a fresh quart, op should have just used another vehicle to buy what you needed.

10-01-2007, 09:18 PM
piston rings could be shot


Mixing oil weights or even brands won't make a car smoke. What will make it smoke are parts in bad/worn mechanical condition.