Overheating problems

[I_AM_A_NINJA]

I posted a version of this in the ls forums, but i think this forum is more accurate.. basically my dad's car has been overheating, i got the thermostat replaced and it stopped, then yesterday it started overheating again, it wasnt until after i put a tape in the tapedeck(dont ask me why i listened to a tape lol)that the car started overheating again, it said some kind of error, when i inserted the tape and ever since then everytime i turn the radio on or listen to a cd the car will start to overheat, the gauge will go up a bit when i turn on the ac also, but barely, has anyone else had this problem, or know a solution? it sounds like a short of some kind

 

[Redwingvksm]

I'd check grounds.

When it over heats - is that just from the gague or did you do an infra-red detection near the T-Stat?

 

[I_AM_A_NINJA]

just from the gauge, im not able to tell if the car is actually overheating