JoeBentley

My 06 Cobalt (2.2L L61, Automatic, App 45,000 miles) is having an odd overheating problem.

When idling it runs a little hotter then normal, but doesn't overheat, usually in the 180-220 range.

But as soon as you reach road street speeds, say 35 miles an hour, it rapidly heats up to the 250-270 range.

Also the fan runs for several minutes after the engine is turned off.

The oil was changed recently, the coolant levels are normal.

Any ideas?

Sox-Fan

iTrader: (7)

Water pump? Thermostat?

Mr Mall Cop

iTrader: (1)

Maybe a stuck thermostat as the 250 to 270 is too hot

nhanson

iTrader: (1)

Thermostat most likely

250-270 is dangerous

Blast the heater till you can fix it.

BankerBalt

do you have a chain slapping sound under your front cover? this happened to me and my timing chain fell off the gears for the water pump

Powell Race Parts

iTrader: (3)

Put the air dam back on/
problem solved/ ur welcome.

Sox-Fan

iTrader: (7)

It's a Cobalt, not a Corvette John.

The does have a point though, the air dam can make a big difference.

Powell Race Parts

iTrader: (3)

cobalt runs hot at speed with no airdam. all cars have air dams pretty much. for a reason. pulls air through the radiator.