If my coolant is low, would this not supply coolant to my heater core?? my over flow tank is ALWAYS at the half full tank, when cold or hot, but my light only comes on under heavy acceleration.

This probably means there is not enough pressure in the system, Im going to try to buy some coolant tommorow, and see what happens.

I had this theory, and someone else may have said it too, but under heavy acceleartion more coolant is TRYING to be pumped then whats there, which means if the surge tank emptys out, or where ever it goes, the low coolant light would probably come on until the RPM's drop, and the coolant flows slower and has more time to fill up.

Tommorow im going to take a closer look, it looks to me the only way to add coolant is through the recovery tank.

EDIT: After all, if the engine is hot, the surge tank should be FULL to the top, since its expanding due to heat! According to the manual the light comes on when your 3 liters low, so perhaps im border line? I also read in the manual that the fan will not turn on for heat unless the engine is hot enough for the heat to work, so you dont get blasted with cold air. If so, could this be a sensor bad, or no coolant going to my heater core? The fan DOES come on, but a damper closes and all I hear is the fan spinning around, no air coming out of any vents.

I've tried using DEFOG, it channels heat from the heater vents and the wind shield, but I still had no heat even with the thermostat at 90 degrees and a hot engine.:nono:

ok, have you had it pressure tested? i had that problem. it turned out to be the cap. get it pressure tested and the mechanic can probably tell you what is going on. mine still leaks out but that is because i have a leak in the radiator. it holds pressure fine though :hmm: . just cant figure it out.

The cap could be it, I spent 10 bucks on a gallon of 50/50 anti-freeze today, it said I could mix with ANY coolant, it was Prestone something...I filled the tank up while it was kinda cool, been sitting for 2-3 hours, and it was registering at the full mark for being cold, as of right now I put about 1/3 bottle of anti-freeze into the over flow tank, and the level has gone up, when hot or cold.

Now, I also noticed after filling the tank, starting the car, and looking at the pressure tank, there were bubbles coming from the front, like it was boiling on front side of the tank, strange? Maybe it is the pressure cap, I can take the cap off and the coolant is just seen steaming, even after a hot run.

I was revving the engine/giving some gas, I held the gas pedal about 1/4th to 1/2 half way down, and the speedo was reading 6 mph even though im in park and the park brake is on, funny.

I also spilled a little coolant on the engine, I had been sitting after running for 10 minutes, came out with anti freeze and attempted to pour it in, it splashed on the engine and surronding area, a very small ammount. So, now there is a smll of anti-freeze, I went out later and poured some water on the area and flushed it, didnt help.

EDIT: But no, I DONT Have any leaks, or else my coolant level would be lower everyday, it just stays the same, thats the problem.
ok, have you had it pressure tested? i had that problem. it turned out to be the cap. get it pressure tested and the mechanic can probably tell you what is going on. mine still leaks out but that is because i have a leak in the radiator. it holds pressure fine though :hmm: . just cant figure it out.

Carguy16
Didn't we discuss this coolant issue in an earlier thread? Look back through your previous thread for some good somments too.

The low coolant indicator switch is not a pressure switch. It is a simple level indicator contact switch. I haven't torn one down, but it is most likely a float type switch. The coolant system is closed, but has a small amount of air in the top of the fill reservoir for expansion. Pressure in the system increases with heat and expansion of the coolant fluid, not from the water pump. You probably just have a sticky fluid level switch.

Hey, stop buying water with your antifreeze. That 50/50 mix is a lot more expensive than the 100% coolant product. Mix it yourself at home and save some money. The first time I saw the 50/50 mix product, I couldn't believe my eyes.

Those bubbles you saw were most likely just air bubbling up to the reservoir after you filled the system. How did you fill the system, with a water hose? That's quite common, but adds a lot of small air bubbles within the fluid, and takes a few minutes to escape once the water pump starts circulating the coolant. I always fill my system with a large container like an empty antifreeze bottle, etc. Also, if you didn't use the air bleeder valve/screw next to the thermostat housing, you may have had some additional air in the system.

you say the coolant level in the overflow tank NEVER changes ? it should drop when the engine is hot and refill as the engine cools.. check coolant level at the Radiator CAP when the engine is cold ... odds are its low and is not siphoning from the overflow tank