The temperature gauge goes up when speeding and goes back to normal every few minutes, the fans are aparently working. I got a mazda tribute 2008,4 cilinders.

SOURCE: 2000 Nissan Altima temperature gauge and heater problem

sounds like you need to replace the thermostat.

SOURCE: Audi A3 2002 model auto - temperature gauge not working

The guage and fan speeds work on independant sensors. If you can remove the plastic engine cover and locate the "sending unit" for the gauge disconnect it and restart the engine. The gauge should remain cold and not move. If this is the case replace the sending unit. This should be a single wire sender located in the waterjacket of the intake manifold look in the area where the upper rad hose enters the intake.

SOURCE: 2001 Mazda Tribute (3.0 L) Heater motor functions on high only

Its the Blower Resistor....If it was the switch, it probably wouldn't work at all....But the Resistor will give you those symptoms, of working on high med or low

SOURCE: 2008 Mazda Tribute - Radio

Look in the engine compartment for a fuse as well as a relay for your radio.
Could be there where you need to look.Vote if this helps ok.

SOURCE: I have a 2004 grand prix gt my coolant temperature

First off when did this start? Was it prior to the Thermostat replacement or after? What was the purpose of relacing the tstat?

From my experience use only a high quality t-stat that maintains a constant temp. is the best solution, it's easy to try and save a few bucks I'm just as guilty as the next guy however I've had many years of experience in the automotive field, throughout the years I've replaced hundreds if not thousands of t-stats and all are not even close to created equal. My opinion is not to go to the big box stores to purchase an off branded t-stat these t-stats open very inconsistantly and tend to have temps that fluctuate greatly. Commonly these economy t-stats are rated at say 195 degrees however they tend to snap open and closed very fast and erratically causing the temp to suddenly drop and then snap closed when the coolant falls below the opening temp. And again reopen not at the 195 always but sometime not opening until say 205 or 210 and then again snaping open and the cycle continues. Buy a premium t-stat and you'll be glad you did.