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Discussion Starter #1
Hey guys, yesterday I was starting up my truck ('04 / 3.5L) and I noticed a small cloud of blue/white smoke behind my vehicle. Since my truck has never done that before, I thought maybe it was from someone else's vehicle so I kind of brushed it off. A while later when I stopped somewhere for a few minutes and started back up again, I got a huge cloud of blue/white smoke behind me. I had my windows cracked so when I backed up, in got inside the truck and it smelled like something was obviously burning. It happened a third time later that day, but it was a smaller cloud of smoke. It also did it during my first start-up of the morning today.

I don't know what's going on at this point. As I said earlier, this truck has never smoked on start-up or any other time. I changed the oil a thousand miles ago (140k). Checking the dipstick, it does look like it has burned some already though.

Any thoughts or ideas of what might be going on?
 

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Hey guys, yesterday I was starting up my truck ('04 / 3.5L) and I noticed a small cloud of blue/white smoke behind my vehicle. Since my truck has never done that before, I thought maybe it was from someone else's vehicle so I kind of brushed it off. A while later when I stopped somewhere for a few minutes and started back up again, I got a huge cloud of blue/white smoke behind me. I had my windows cracked so when I backed up, in got inside the truck and it smelled like something was obviously burning. It happened a third time later that day, but it was a smaller cloud of smoke. It also did it during my first start-up of the morning today.

I don't know what's going on at this point. As I said earlier, this truck has never smoked on start-up or any other time. I changed the oil a thousand miles ago (140k). Checking the dipstick, it does look like it has burned some already though.

Any thoughts or ideas of what might be going on?


You are burning oil due to a few possible reasons such as explained here...

Blue/gray exhaust smoke is an indication of oil burning in the combustion chamber. These are possible symptoms and causes:

Valve Seals: Leaking valve seals will cause blue/gray smoke at startup because oil leaks past the seals into the cylinder after the engine shuts down.

Valve Guides: Excessive clearance between the valve stem and the valve guide allows oil to leak past the gap into the cylinder.

Piston Rings: Worn or damaged piston rings will cause blow-by resulting in blue/gray smoke.

Worn Cylinder Walls: Worn cylinder walls cause blow-by resulting in blue/gray smoke.

PCV System: A stuck closed PCV valve will cause excessive crankcase pressure resulting in blue/gray smoke


Exhaust Color Diagnosis | White Smoke Blue Black
 

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Discussion Starter #4
Thanks for the insight Will. If I take it to a mechanic, what kinds of tests would they run to nail down the problem?
 

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my first thought would be head gasket, but im sure someone else has had this problem and be more help
White smoke is usually antifreeze getting into the cylinders and burning. So it's possible as well that the engine is also burning oil since he said his dipstick shows oil went down and the exhaust is blue white?
 

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Thanks for the insight Will. If I take it to a mechanic, what kinds of tests would they run to nail down the problem?

If you take a hour and remove the 5 spark plugs to examine them - they should be clean but if they are gunked with oil deposits or soot then you certainly have an oil burning issue. If you have a friend with a cylinder compression test kit or you go to Sears or autoparts store you can purchase a basic kit for under $100. Harbor Freight has cheapo kits for $50. Since you have the spark plugs out run a compression test on each cylinder. Compare your readings of each cylinder to see if there is huge drop on one or two of them - then this will be where the problem lies. Check what the factory compression PSI should be to compare also. A compression test will tell you if your cylinder is losing compression or something is leaking - ie bad rings, worn cylinder walls, leaking at the valves or valve seats etc. If there is a compression problem with one or more of the cylinders then this = a big repair bill.

Good luck.
 
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