just finish breaking in my street port motor.....problem #1 my stock temp guage dont work...need to kno what to check or should i just buy aftermarket one problem #2 in the day time my radio and stock tach is fine until nights time when i have to turno on my head lights my radio turns on off on off and my tach fails why??

 

Only get a Mazda OEM thermostat. Your current tstat might need replacing. Sounds like you have a weak charging system or bad grounds. How many volts are you holding at idle? A fix for the alternator is upgrading to an FD alternator. PM silverrotor. Look at the sticky on the top of the page for grounding tips.