Rep Power: 0

I have a 2002 Civic with a d17 new radiator new radiator cap new thermostat new overflow coolant resivor tank and after driving it for about 15 minutes it runs hot and builds up alot of pressure inside the radiator and pop my overflow tank hose off but when I open the radiator cap the temperature goes back down then start back driving the temperature goes back up I have no milky resido on my oil cap or stick

 
Rep Power: 175

So you open the radiator cap while the car is still hot?

Read ALL of this. https://www.civicforums.com/forums/3...reference.html

Then do the tests. If you let your engine get ALL THE WAY to hot, you might have to get the head machined.

 
Rep Power: 245

Probably head gasket. Common 7th gen issue.

 
Rep Power: 230

Check your fans as well Mine blew a fan switch at 165,000km. If it's overheating when you pop the hood the fans should be running full blast, if not you need a new fan relay, switch or fan it's self.

Also you could have air in the system, after replacing the thermostat did you do a forced flush with a rad. machine? Once air gets into the system form being low it can stop the coolant form flowing properly. Im not sure if this problem is around with that vehicle it all depends on the cooling system layout and if air can form a pocket.

 
Rep Power: 187

Blown head gasket. Rad fluid and oil will not mix in this engine to show a blown head gasket unless things are extremely bad. It's a known issue as stated before. Get the head checked and machined if necessary and install a new head gasket. I recommend OEM, but that's up to you. Good luck.

 
Rep Power: 175

I read that you kinda "burp" ours by raising the front tires only when you do it. Also running the heater full blast beforehand.

 
Rep Power: 519

Ya don't HAVE to do it that way but getting the nose of the car up high enough to make the radiator the highest point in the cooling system (or at least higher than normal) sure speeds things up in the shop for me.