some help please ,i have read here that my temp should stay at a 1/4 mine is at 1/2 and climbes to 3/4 in regular traffic ,if i get on the highway the temp returns to 1/4 or just a little above that.i replaced the thermastat with a mazda oem ,i still have the same problem.in the pic i posted there is a sensor near the thermastat ,it looks like it has a small crack in the red part of the switch.could this sensor cause this problem it is not leaking and also the coolant by the cap is not leaking i overfilled it and it dripped out ,the cap is new.the car is an 88 t2 it runs good and does not blow smoke the coolant system is full aslo how can i tell if my fan is operating properly .

 

you have auto transmission?

 

no , manual

 

Sounds like maybe your radiator is cloged and only becomes efficient at high speeds, or your fan isn't operting properly. When engine fully warm the fan should be moving pretty fast and rev with the engine, you should be able to hear the air moving through fan.. when cold should just free spin. Pick one up from a junker for about 10$ and see if that was your problem.

And since he said T2 and is located in the states, so he should have a 5 speed manual.

 

then maybe you don't have to worry about the red top sensor being crack/but not leak

 

Sure sounds like a fan problem when your idling and the tempeture starts to rise open the hood and see if the fan is blowin. Also while its hot see if theres any steaming coming from the gasket that you replaced when you changed the thermostt. If theres even a tiny leak there it will cause a drop in pressure in the system and cause the car to easily overheat.

 

Thanks for all the replies , i did what tom said i checked the fan ,i thought it was working i did the spin the fan test when cold and hot.i read somwhere that was not to reliable,so i let my car start to overheat and i stuck a rolled up newspaper in the fan and it stopped the fan right away, fan clutch is bad .dam this part is real expensive and i dont think there is an aftermarket replacement for it i have been searching the web for one .since these cars are from the 80's i dont know how reliable a used one will be.so as tom said if your car overheats driving around town ,and returns to normal temps on the highway like mine did check your fan.

 

Tear that **** off a car at a junkyard. You can get almost anything there at a fraction of the cost.