coolant temp sensor?

I am having some problems with my 99 z71 5.3 w/ 130K on it running hot. I have owned the truck since october and never had a problem with the temp. It would always sit right under 210 on the gauge. About 5 days ago the temp got up to about 240 (so the guage says). So what i did was put a 160 stat in it only because i had one laying around form another car. I also put some water wteer in it.... well it didnt help at all. I would still get hot when i not moving. Then i changed the clutch on the fan... well that did nothing also and not the fan is fully inguaged all the time! and it very annoying and loud. I dont know if the water pump is going bad, its not leaking or making any noise. Can the temp sensor be bad?? When it get hot it is a little sporadic and when i pop the hood i would expect it to be super hot, but it not...

any suggestions???

Thanks

I am having some problems with my 99 z71 5.3 w/ 130K on it running hot. I have owned the truck since october and never had a problem with the temp. It would always sit right under 210 on the gauge. About 5 days ago the temp got up to about 240 (so the guage says). So what i did was put a 160 stat in it only because i had one laying around form another car. I also put some water wteer in it.... well it didnt help at all. I would still get hot when i not moving. Then i changed the clutch on the fan... well that did nothing also and not the fan is fully inguaged all the time! and it very annoying and loud. I dont know if the water pump is going bad, its not leaking or making any noise. Can the temp sensor be bad?? When it get hot it is a little sporadic and when i pop the hood i would expect it to be super hot, but it not...

any suggestions???

Thankshi did you every find out why i have a 91 Chevrolet Camaro Convertible same thing but my goes all the way in the red but i dont over heat let me no thanks [email protected]