My car keeps over heating and building up presure in the water reservior, plus keeps steaming?

i thought i had a simple water leak but then it went on to start building up pressure where the water hose meets the engine from the Radiator so i changed the hose and it went to do the same. it now just keeps over heating while sounding like the water reservoir is ganna explode. i open it up then the hissing dies down then were on are way 4 five mins then have to stop. please help
My car keeps over heating and building up presure in the water reservior, plus keeps steaming?
thermostat stuck shut and/or clogged up,or worse head gasket blown and/or leaking. check both and inspect water content for oil and check oil for water content..take to professional if doubtful.
My car keeps over heating and building up presure in the water reservior, plus keeps steaming?
Reverse flush the radiator,Change the thermostat.
and take it to a mechanic
Have a pro. look at this issue.
I am currently having similar problems. check out my question about mine. there are alot of great answers there. mainly from user: krazybob



http://answers.yahoo.com/question/index;鈥?/a>
I would bet you your thermostat is stuck in the closed position. Thus not letting the coolant circulate from the radiator thru the engine. Pull the old thermostat and put in a new one. Pretty easy job to do even for an amateur and they don't cost much. Better than cracking your engine block.

You could check the thermostat after you pull it out by putting it in a cold pot of water, it should be in closed position. Put pot on stove and turn on HI to boil. After reaching a boil, use tongs to pick it up and look at it. It should now be in the open position. If not, it's broken and that should be the problem. Make sure you wash out that pot real good.
Sounds to me like your thermostat
had the same problem with my wifes 2000 focus.took it to ford,hudge wast of time.we found the problem. it was the water housing,the thermistat connects to it.made out of plastic!! and with more reasurch we found they only last for about 80000 miles
If you have used radiator stop leak, you problbly have a stopped up radiator. If not it may be as simple as replacing the thermostat.
You need to get the Cylinder head off - change head gasket.

Hopefully it's just a failed gasket. If it fails again - it may be a cracked or warped head.



The pressure is from the cylinder leaking into the waterway - which then pressurises the water. Symptoms are lots of foam or bubbles in the coolant tank.