Chevy Malibu 2000 Ls burning Oil on all the cylinders

Maintenance/Repairs
1

Hi Guys:

I have a 2000 Chevy Malibu LS 3.1 V6, the car is burning oil, and I want to know your opinion.

The car had thermostat problems and was overheated, after I changed the thermostat the engine started smoking and every body told me it was the head gaskets, but the car is not burning coolant, is actually burning oil.

When I start the car, first is the steam coming up from the tail pipe, then when the car is warm, the oil smoke stars to come out from the tail pipe.

I checked the spark plugs and all six showed a lot of oil on them, so my question is, is this because the piston rings or the engine is getting oil from somwhere else beside the piston rings.

There is times when is not smoke at all, and then again a lot of smoke.

In the past I saw cars burning oil from probably one or two piston chambers, but no from all of them at the same time, and on this one when I checked, all the spark plugs were wet in oil.

I was researching about this particular engine, and looks like have some issues with the head gaskets due to overheating and the fact of the heads being made from aluminum.

Please can you tell me what can I check before taking the engine apart.

Thanks

Hector G.

2

Look at the oil on the dipstick. Does it resemble a chocolate milk shake? Are the plugs covered with black oily sludge? What are you seeing that makes you certain that oil smoke is coming out the tail pipe?

3

Rod Knox:

What I did so far is this, repalce the thermostat, changed the old spark plugs for new ones, change the fan relay, checked the oil looking for the chocolate kind tipicall when you have water or coolant inside the engine, and when I checked the dipstick, the oil is dark but no water/coolant on it

4

The first step is to perform a compression test, both dry and wet.

Overheating can ruin piston rings because of any one of a number of reasons, or all of those reasons combined.
Coked oil in the ring lands, scored cylinders, seized rings in the lands due to heat, or the loss of temper in the rings; meaning the rings have lost their springiness.

Overheating can also ruin valve stem seals but there is no test for that.