temp gauge problem

[rbpwr]

quick dumb problem, sometimes while im driving i notice my temp gauge is acting like a reversed boost gauge.... i step on gas or cruising and it goes to cold i let off it climbs right back up and it does this quickly, thats why i say it acts like a boost gauge, any suggestions on what to look for as to im stumped. again this only happens once and awhile...rb25det series 2

[lazysk8er2]

is this the stock temp gauge in the cluster? or aftermarket?

[rbpwr]

stock one in cluster

[NismoS13Ks]

could be your temp sensor. grab a new one from courtesey parts their like 3 bucks.

[rbpwr]

is there any cars that mine would be the same as this motor? ie 300zx?