Noobie here lol... got a evo 8 RS about 2 weeks ago and its been great! (had a Cobalt SS before)

But i noticed on my drive home last night my coolant temp would rise to almost the H then drop back down.. And when the A/C is on its towards the H more then when its off... Now i did some searching and I think its the thermostat.. just wanted some other opinions before i spend $$

Thanks in advance

 

bleed the coolant system, start the car from a cold start with the cap off and let it run untill the fan kicks on. keep an eye on your temp though

also, check your ground on the intake manifold that bolts right under the strut tower.

 

Thermostat will cost about $60-$120 depending on if you go stock or aftermarket.
I had the same thing happen to me. Try not to run the car now that the internals have probably expanded due to it being overheated. Shortly after about less than a week my piston blew thru my oil pan..
Make sure your fans are kicking on. check the solenoid near the intake. It should have a black and blue wire protruding from it and have the check to make sure proper voltage. Check your radiator to see if there are any leaks, replace your radiator cap if it is not holding the pressure, change out your upper and lower radiator hoses if there are any cracks.

 

can i not get this thermostat??

http://www.mitsubishipartscenter.com...gramCallOut=20

ITEM 20

 

Item 20 is what you need! I believe it comes with the gasket too!

 

Could also be a ground

 

which cap do i take off?? radiator cap? or the coolant tank cap??

 

Take of the radiator. Coolant tank cap is just for the overflow. Car doesnt smoke at all does it?

 

car drives fine and idles fine with no smoke.... which means its not a head gasket right??

when i get off work im gonna try to burp the system

 

right your head gasket should be fine then. one trick that i know you could maybe to is take out the thermostat and put it in a pan of boiling water to see if it is function properly. But if you do that you may as well just replace it anyways as you already have it out. Good luck

 

Thanks!! i dont really wanna pour money in the car i just got i already gotta buy tires for it this week

 

radiator cap!

 

burped the system on my lunch break... gauge didnt go above the normal temp like it did before...we will see how the car does on my way home...

 

On top of the burp, check if your radiator fan is working and turning on when you turn on your A/C. Also check if you are running a slim fan, this will not cool your radiator as well as an OEM fan due to the size.

 

well the temps still go high.. 75% up the gauge... should i burp it again?? or get a coolant flush?? or just go ahead and get the thermostat??