The radiator doesn't have a cap. The overflow reservoir tank has a cap instead. (Tan plastic tank on passenger side)
Have it pressure tested, the intake gaskets have probably failed.
just follow the upper radiator hose to engine, and you will find it.
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You can find a water flow cooling diagram for a 2002 Chevy Malibu in the car's owner's manual. You can also check with local auto part stores.
follow top radiator hose to the end, there is the thermostat in housing on end of hose. on 3.1 v6 it is under exhaust manifold! it looks like it would be hard to change but it can be done.
the thermostat will be under the THERMOSTAT HOUSING, which is where the TOP radiator hose fits on ie(radiator to thermostat housing) this keeps the engine at an OPTIMUM temperature BUT can be A cause of OVERHEATING IF malfunctioning
The 2002 Malibu had a factory recall for a defective turn signal relay. Replace and it should work fine. If you can find paper work from GM about the recall, a GM dealership should do it without charge.
Under the hood of your Chevy Malibu there should be an engine information tag which should suggest the proper spark plug gap. If you cannot find the tag refer to your car manual that is normally located in your glove box.
go to kbb.com
where is the fuelpump on a Chevy mailbu
In your owners manual.
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