Ok here is the deal guys, I just got an 88 iroc and the temp gauge on it does not read correctly, when ever I turn the car on it just simply goes all the way up to the red zone and it is constanly moving, it never stays still and give me a steady accurate reading. Ive posted a link of a video on youtube so you guys can see exactly what it's doing....... I know that the car is not overheating because it always does this soon as you turn the car on even if its been sitting overnight. It has to be a problem with the gauge.......

http://www.youtube.com/watch?v=AoFyo...ature=youtu.be

If anybody knows what could possibly cause this problem please do not hesitate to leave a comment, I really want to get this fixed.... Thanks

Gauge or sender - disconnect the sender and see if the gauge settles down.

What and where is the temperture sender?

The sender is the thing that senses the coolant temperature, that the gauge reads. If I am correct, the stock location is on the driver's side (left) head, between and below plugs for cyls 1 and 3.

Pop the connector off it, see if the gauge stops flickering. If so, sender is probably fritzed, if not then it's the gauge or wiring to the gauge.

O you mean the sensor itself, yea I replaced that but it was with one that wasn't new and I believe that it does stop when the connector isn't connected

yea so I went out and checked it and it does stop moving like that when I disconnect it so should I just go buy a new sensor??

With the wire disconnected, the gauge should read solid zero. Ground out the wire, and the gauge should read solid over full scale.

If this is the case, the gauge and wiring to it are ok. The fault is then the connector to the sender, the sender itself, or the sender not making a solid ground connection where it screws into the head (unlikely).

Most likely the connector - plug it back in to the sender, and have someone watch the gauge while you wiggle it. See if it settles down then.

The sender is the thing that senses the coolant temperature, that the gauge reads.

I actual replaced the gauge with a couple I got from the scrapyard so I don't think it's the gauge, when you say wiring, what wiring are you referring too?

There's only one wire, the one from the sender to the gauge. Did u give it the wiggle test?

Yea I wiggled it around and it seems to be doing the same thing, sometimes it would just stop wiggling and either just settle at the very top of the gauge or the very bottom but it wasn't actually reading the temp

Time for a new sender.

Ok I just replaced the sender with a new one from autozone and it seems to be doing the same thing... Does anybody have any other ideas what It could be??