My plastic reservoir is full, when I drive for 10 min I get the eng light on.. Is it the water pump or radiator that needs replacing.. Also I have to put anifreeze in every week
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1999 GMC Jimmy Question: Overheating
Answer #1ziptie12 July 05, 2012, 15:40Master
Get it diagnosed properly for either a stuck thermostat ,bad fan clutch ,blown head gasket.You state that your plastic reservoir is full ,when you drive for ten minutes .Was it empty or low before you start and does it empty out (sucked back in engine/radiator) after it cools?From a cold start (after sitting over night) check the radiator level , make sure the system isn't pressurised , then start it and check the top hose at a safe point.If you can feel bubbling or if the hose is feeling 'tighter' very rapidly (within a minute or two) MY opinion would be a blown head gasket , just get a second opinion before you spend any money (other than coolant for test purposes).Go backwards and re-check the obvious , which we all can often overlook in our initial haste.Good luck.
Replypushrod, July 05, 2012, 18:04Master
Don't forget about a simple combustion leak test! Most any repair shop can do
Replyziptie12, July 05, 2012, 20:20Master
YES ,that to.