Yesturday when i was driveing home i looked down at my temp gauge and it was at 260!! I was like *** ****!! I pulled over and checked the engine it didn't seem to hot it just seemed like normal. I drove it home with no problems. I let it sit for like a hour and a alf and had to pick up my sister. i got in the car started it up and it was still pinned, So i took my other car. When i went to school today i started it and it was spikeing up and down to 220 then after 2 minutes it just spiked all the way up to 260 and stayed there. The heat wasn't even workeing yet!!! I got to school poped the hood and put my hand on the radiator cap and it wasn't even that hot!! I think this has to be a sensor but what sensor and were is it??

 

Anyone??

 

I am going to assume V8 TPI...

On your driver side head, between 1 and 3 exhaust ports (front two) there is a brass sensor with 1 wire going to it. That wire is green if my memory serves me correctly. Make sure that wire is connected and not grounding on your frame or manifold. That should fix you up! It doesn't sound like a real overheat problem based on the information you gave me.

 

I see LG4 in your avatar. I believe the location information holds for your vehicle but I'm not certain still on the color of the wire.

 

Sorry its a carbed 305 v8 And i don't hink it is over heating it's just worrying me that it is reading 260..
And i don't think that my fan is comeing onwhen the temp said 260 i checked to see if the fan came on and it didn't so i checked to see if it was getting power and it isn't, the fuse is good and the fuse block has power. Maybe its just that thing you described is makeing the tamp gauge read wrong!

 

Sounds like a grounding out problem to me

Ryan

 

the very best route you could take on the matter regardless of what anyone says, is install an aftermarket temp/oil gauge...

mechanical of course... stock gauges from chevys can be very misleading... also your thermostat could be sticking...

but a temp gauge is easy to install, just tap into the side of block (perferably the side of the block for best accurate readings) but the intake somewhere can be a other place to tap the gauge into(some people say the gauge will read accurate there, some wont..)

 

Is it still pinned when the car is off? Something similar happened to me, and it turned out to be pretty stupid. The guage was wedging beneath the plastic and just getting stuck. A little twist tie pushed in beneath the dash pushed it back out so it would work.

 

if its stuck up there just thump at the gauge. thats what I used to do.

 

i had an 84 camaro that it pegged out and would stick at startup every time, guage was worn out, time for new guage, common problem with these

they are designed so that the ignition sends ground to the gaueg for a second at startup every time, some kind of test i dunno, its stupid though, something they started doing for the 80s