here the deal... park the car, turn it off and i hear the bubbling... dam... overflow is boiling over, let it do its thing. got a new rad cap, filled the rad back up and let it run for 10 minutes (till it started to rise.... and it rose so much it was about to overflow out of the rad, i think this is normal) anyways, a couple bubbles pop out... opps.... so then i check the heater... nope no heat.

so today i drive to school (30mins) and still no heat, but i go to come home an hour later and bam. hot hot air. hmmmmmm..... so whats the problem?

temp gauge has never gone up past half, engine seems fine but underhood is somewhat hot.

thanks.

 

Did you have the the heat control in the hot position (NO FAN) when you purged the air. Also let the car run till the fan comes on twice to be sure it has fully warmed up. While the fan is on the second time fill the radiator to the top and put the cap on. Make sure the reservior is full too. Sometimes a blown head gasket will blow the water out of the heater circuit, no heat, while the car appears to be hot.

 

yup i ran the heat full blast will i purged the air

 

Could also be a clogged heater core also. There will be 2 hoses going through the firewall heat up your car and grab onto each of them if one is significantly hotter than the other your heater core is clogged.

 

for your temp. gage! just check your temperature coolant sensor! check the resistance on it! mine is freaky since a couple days!

when engine is cold: 142 ohm
when engine is hot: 49-32 ohm

these are the specs for a good sensor!

 

Most of the time a bad headgasket will "bubble" or "overflow" out the the radiator....not saying thats the case with yours though. Possibly your thermostat is not opening or not all the way....check that.