can someone help, i changed the thermostat/ did a rad flush/ made sure the fan runs fine. but going up hills it heats right up. from what i can find it may be a water pump problem. is this correct? also where is the erg valve located as i have idling issues when coming to a stop. like others on here it wont stall but drops right down then comes back up again. thanks in advance for any help!!

The impeller may be spinning on the water pump. I had that issue once.

Was there any rust or rusty coolant when you did the radiator?

If there was, you might want to pull out the thermostat and do
a back flush of the engine, which is putting water into the top
and letting it drain washing out any rust that could be blocking
the small coolant passage holes in the head gasket, but in my
opinion, I also think it's a spinning impeller on the water pump

Wild

No everything was clean but i'm not sure what you mean by the impeller spinning?

The impeller or fins inside the water pump will become loose on the shaft and spin. The fins will actually not spin thus not pumping water. The impeller is pressed onto the shaft and can become loose. The shaft will just spin inside the impeller.

So you should try replacing your water pump.  Put a new timing belt and front seal on while you are in there.