Hey guys, Overheat /overflow boil over at idle, thermostat new, water pump new 7/16, never heat problem before with the exception the fan would come on after key off, ran for 5-6 min. Now fan issue may be point of interest, will operate with a/c on, but intermittent with a/c off. Thoughts are ECT sensor malfunction... looking for any other possible causes, any ideas?? .

 

we had a S70 come in onetime with a cheap aftermarket water pump that actually had a broken impeller - otherwise - I'm thinking head gasket

 

Thanks for reply ! Yeah, it was after market... all I could afford at the time .
Not getting any unusual noise from there...

 

Sounds like either a bad water pump, or possibly head gasket. Start it with the cap to the coolant tank off. If you get bubbling or exhaust fumes with the engine running you had a blown head gasket. If not, I would look at the water pump.