I got a problem with my toyota tamaraw 7K engine car particularly with my temp guage. Onetime after few minutes after warming it drops to zero. Sometimes it happens while running. From zero (after it droped) it will go back to a certain reading. I have an idea of installing a separate temp guage but I'm not familiar with the type of temp guage replacer.

Is there any relationship with the termostat? My mechanic adviced me to remove it, is it sdvisable to do so?

thanks my friends