normally my temp gauge will indicate at the normal line between 100 and 220, but sometimes it just climbs up and pegs then comes right back down, this happens once every few days, could it be the sending unit (where is it??) or the thermostat itself sticking??

------------------
91 RS 305 TBI
hypertech chip
160 deg stat
flowmaster exhaust
gutted cats
Z28 grille and fogs
freshly repainted mystic teal (the orig color)

 

I'm having the same problem, for some reason it only seems to happen when I've run the car a short distance, or am stopped at a light. I already tried to change the gauge, and for me it wasn't that, I think it might be the sending unit... The sending unit should be around the number 1 and 3 cylinders, on the underside of the car, near the front of the engine, if you figure out the problem email me at burnblues@hotmail.com and tell me about it, I'd like to know what the problem is, I'm at school so I can't diagnose it myself...

 

CG,

If the guage pegs briefly, then returns to normal, it might be the sending unit. Or it might be that the wiring to the sending unit is momentarily grounding, causing the maximum reading to be displayed. The wiring is routed relatively close to the exhaust between the #1 & #3 cylinders, so that might be something to look for.

If the thermostat were sticking closed, the temperature would probably climb gradually, then fall rapidly as the thermostat opened. If the guage indicates a rapid climb then fall, I'd check the wiring and sensor first.

------------------
Later,
Vader
------------------
"Make Me Bad"
Adobe Acrobat Reader 4.0