oil in coolant on 1999 Chevrolet Cavalier

i just bought a 1999 cavalier for 100 dollars and it has oil in the coolant tank it runs real good and does not overheat any ideas

by in Woodstock, IL on September 09, 2009
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4 answers 1 comment
ANSWER by , April 23, 2010
if you have oil in your resivior, it means somone poured some in there by mistake,,but im more leaning toward a blown head gasket. it will run fine but you will have to keep the water clean out. to fix it buy a head gasket and surface the head..you have a blown head gasket.
ANSWER by , September 09, 2009
Thoroughly flush out the coolant expansion tank and cooling system, radiator , engine block ect... with a commercially available cooling system flush (Prestone or any other brand). Oil will damage the rubber cooling system hoses. Refill the cooling system with the correct amount of fresh antifreeze and drive the car after the cooling fans have cycled on and off. When the cooling system has cooled down top up as required and keep an eye on the cooling system for a few weeks to see if the problem reoccurs or if someone had inadvertently put oil in the reservoir.
ANSWER by , May 06, 2010
i wouldnt count on it being "accidental", it may be one of your intake manifold gaskets, also check oil for coolant, if you have oil in the coolant, its defenatly your head gasket, i recomend a full flush, block, radiator and resouviour.. then if the oil returns, you have most likely an intake manifold leak, also possibly head gasket, BTW, if you bought the car for 100$, DIY
COMMENT by , October 22, 2010
How can an intake manifould gasket failure put oil in the coolant?
ANSWER by , October 22, 2010
Pressure test the head. Fit a new head gasget. If not good, replase the head and a new headgasket.