Question about 1999 Oldsmobile Alero

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1999 Olds Alero leaking coolant and running rough

Our daughter has a 1999 Olds Alero that she bought used about a year ago. Right before Christmas she noticed it would be losing coolant and occasionally overheat or run hotter than normal. At times it would run rough like it was missing too. After pouring over a repair manual her father decided it sounded like an intake manifold gasket. He replaced that and the resevoir cap and it didn't overheat or lose coolant for about a week but started to run rough again. He noticed that the new cap went on and came off quite hard. Now today our daughter called and said it overheated again but isn't running rough anymore. All she had done was put the old resevoir cap back on since it was easier to do. Please help! Is it possible that there's a fan problem? She said it was working when she checked. Can they go on and off due to a fuse problem or anything like that? Thank you! Pat Myers

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  • CJ Kelly Feb 14, 2009

    My 1999 Olds Alero just started doing the same thing, I have replaced my water pump and the thermostat, I did find a cap that worked but it did not fix the problem either, please if you have heard anything about your daughters car, please let me know.



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In my experience it sounds like a head gasket problem it maybe leaking into the cylinders or could be a small leak from one of the hoses I would do a compression test just to make sure and then pressurize the entire system using radiator and coolant tester if pressure holds then its not a leak as far as the fans go just have the car running when it reaches the middle of the temp gauge it should come one if not you may need to run check on temp sensor or fan switch and fans them selves I would follow repair manual troubleshooting section on heating and cooling haynes or chiltons will do.

Posted on Feb 26, 2009

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Bleed air out of cooling sytem .when you replace water pump or radiator. if you dont bleed air out it will over heat.

Posted on Mar 22, 2009

  • Jonah Oneal Mar 22, 2009

    remove thermostat and radiator hoses from water pump flush out engine block . and radiator . dont use too much water pressure . flush from the top where thermostat goes flush until water come out clear and a nice size stream .catch water from bottom where water pump hose goes . put in new thermostat fill with new coolant . bleed the coolant . before starting procedure . take flash light check down radiator where coolant fan is. if it look wet down bottom of radiator . its leaking or the hoses are leaking.



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