ok well.. check this out... i start my car.. let it warm up all the way to the middle of the Temp Gauge which is the normal temp and good. ok fine good... so i roll outta the drive way and like 15 secs later the Temp needle is at like H.. ok wtf.. so i continue to drive and it dies down back to middle like in 15 secs... ok all is good... meanwhile this is happening i know the coolant is being pushed outta the system and into the overflow... i stick my finger in the overflow.. Coolant inside the tank is cold... so wtf?

next after that i pop open the radiator cap.. slowly.... and steam aplenty... and also hot coolant... so what gives?

its not a blown coolant seal because i did the Geyser test as well as the exhaust check.. doesnt burn coolant neither.. my guess would be maybe air in the coolant system.. if so how do i get rid of it.?

my car is a 1989 GXL...

thanks guys

 

It's probably your thermostat. Is it mazda OEM?

 

yeah... i just put in a new thermostat like 2 monthes ago....its Mazda OEM.. i realy dont wanna spend more money on this car as iam trying to sell it.... so i dunno.. anyone else?

 

When the car is warmed up, feel the upper radiator hose if it's hot. If not, the thermostat is not opening or you installed it backwards if you just installed it.

 

X2delight mine was doing the same thing and then I lost a coolant seal. It would start then go to hot then cool down. Not sure what the problem was but it cost me a rebuild.

 

it may be your fan as well, my car would do this i i realized that my fan wasnt switching on properly and i also had some small coolant leaks, i put in a new Koyo radiator, it runs great and holds its temp right or a little below the halfway point on the guage and Im not running a fan either. Check your thermostat as well as it could be that too.