My car has been acting a little weird lately. Ive intermitantly had a low coolant light on in the dash. I had the coolant system flushed out a month ago and after the system was flushed the low coolant light was still on...thus bad sensor correct? Now all of a sudden the car heats up very fast to about 220 and stays there with no difference in traffic or on the highway. Today I tried to turn the heat on and it only blows cold air? The coolant level is fine so whats up? Is it the heater core? Thermostat?

 

There's probably some air trapped in the system. You should try bleeding the system once it's cooled down.

 

if it heats up fast then that really sounds like you are low on coolant. have you looked in your radiator? that'd be a good place to start.

 

the coolant isnt cycling through the block...like someone stated above...you probably have air in your system...thats why when coolant is being added (with the car running) you are supposed to loosen the valve on top of the line by the waterpump and i think there is another one on the other line as well...loosen those up while adding and that pushes and releases the air out...and also allows you to fill it up all the way with coolant. (BEWARE - WATER WILL SQUIRT OUT) So have a rag nearby and watch ur eyes.

Cory

 

Which is why it is a better idea to have the t-stat and heater core bleeder valves open, pooring coolant in w/ the engine off. as the system fills you will hear a hiss in the bleeder valves. close the t-stat bleeder when coolant starts to run out. keep pouring and close the heater core bleeder screw either when coolant starts to run out of it or when the radiator finally fills up. start the engine, keep radiator cap off, watch guage, let system pressurize by capping the radiator, watch guage, loosen the t-stat bleeder and close either when coolant runs out or system pressure is drained, repeat, watch guage, do the same w/ heater core bleeder screw. fill radiator only until you can see coolant. this way it will not overflow when the coolant expands. if coolant overflows from radiator then cap it and let system pressurize. once you see a steady stream of coolant running out of the steam pipe into the radiator you'll know the system is basically bled. check heater core bleeder valve just to make sure.
it's really easier than it reads.

 

you can do that too...I only do it with the car running cuz I thought I read somewhere that the engine needed to be at operating temperature for some reason?

Cory

 

not at all