antbody know why my car is overheating? My waterpump works, thermostat works, coolant is not spraying out, but the needle goes right to the top in about 15-20 min.

 

Is that while driving or at idle? If at idle, does the clutch fan kick in? This can be checked by just listening to the fan. It will get alot louder due to it pulling the air more than when the fan is just spinning at the cooler temps. Which thermostat are you using? How did you check it to make sure it is working? New hoses? Lower hose have the spring in it to prevent colapse under load? What is your mixture of coolant and water? Has anything been done to the car recently? Stock plastic shrouds on still underneath the car?

 

I had the exact same problem with my car for a little while but there were a few steps I took to fix it.

1) Get new hose clamps (Coolant can leak out and you can actually lose pressure.)
2) Flush out old coolant and get new one. (You never know!)
3) Depending on how dented up and pretty much messed your radiator is, you might want to think about getting a new aluminium one. (One thing I noticed about the stock radiator is that although the radiator is awesome, many pieces of it are plastic. I was told through a good mechanic friend of mine that the all aluminium ones are just more efficient, plus easier to pull and inspect if necessary)
4) Check your seals around your thermostat. (Mine leaked like crazy for a week or so. Since the metal around the thermostat is hot, the coolant pretty much evaporates instantly on contact. Look for green stains around the seal.)
5) Don't get anything but mazda thermostats. For some strange reason, all the aftermarket ones don't work as well. *shrug.
6) This last step was basically a general thing to do to cars if you're worried about overheating but it increases your chances of POSSIBLE damage. Take out the lower protective bedpan. It's connected with a whole bunch of 10mm *i believe bolts. This will increase airflow to the radiator and also the engine so it'll cool your engine much faster and more efficiently.

Alright, good luck!

Peace,
AJ ^_^

PS: One last thing I left out. I have mixed feelings about this so I'm in the process of trying it out. I HEARD that water wetter is a useful tool to decrease tempurature but then again, I heard that it could damage your engine. This would be the first time I've ever used water wetter so I'll get back to the board and tell you peeps how it goes! ^_^

 

I have been using water wetter for years with no problems, and I have actually seen up to 10F less using it.

 

thats what happens also when your coolant nver reaches pressure my rotary started doing it on the intake side and i could tell it ran great just kept getting hot ,also theres a small hose on the back of the throttle body that can leak small amounts and will dry up fast enuff you cant see the leak unless it running and your in the engine compartment lil 11.00 hose and 2 hours of hard work can replace it .it connects the throttle body and the block together i believe it flows coolant from the block to the tb as part of the emissions side of things ...didnt care after i fixed the leak

 

Make sure your temp gauge is working properly. I've had this problem for a year and it ended up being the stock temp gauge. I just finished installing my new temp gauage and when I was testing it, I compared the two. While the aftermarket one reads at 180, the needle on the stock gauge is above 3/4. I think that's too high for 180. I suggest that you take readings using a water temp meter or something like that.