I just installed a new intake manifold gasket on my friends 99 si and when we did it alot of coolant came out and we took off the coolant temp plug to get to one bolt. We took it for a spin and he has no heat inside the car and the needle just keeps going to hot??? he is going to get a new thermostat right now so we can install that, i searched and it seems like that was mostly the prob but why would it just go? I thought it may of needed to bleed the cooling system but when we started the car it pulled the fluid from the over flow tank, but also how do i bleed the coolant??? can anyone help i need to finish this tonight thanks

 

You just have air trapped in the system. Run the car with the cap off for a while, top it up as needed.

 

just did it wirks fine now thanks