My temperature guage just started acting weird. At an idle temp is fine. When driving, if I accelerate the needle jumps all the way down to cold. Take my foot off the gas and it goes right back to normal. Anyone come across this before?

Never heard of it going down on accel... hmmm. I'll have to think about that one.

Thats Wierder Than Jason's Towing/cruise Control Issue

since the guage is electronic, then i bet you have a short of somekind. have you done anything to the electrical system lately?????? if so, backtrack and see if you crossed a wire or somthing or the switch for the temp is grounding out when you step on the gas. which means it prob grounding out by the alt which increases the current when at a higher idle, and my guess is that.

mine does this too... It just started getting worse though. Now, it doesnt come back up when i stop... it flickers a little but thats it.

Where is the sending unit for these things?

I haven't done and electrical work to mine (or any work period haha). The only thing that I did was spray the radiator off with a high pressure wash when i was having an overheating problem at idle.

any ideas?

Usually they go to "hot" when grounded so that is unlikely.

The temperature senders are at the front, top of the engine. There are two of them. You need the one with one wire, the other is for the engine management. Taking the wire of the sender and grounding it should make the guage go "hot".

Do you have a manual? What year is your truck.

Mine's a 2003. I dont have a manual.. :(

I'll check that wire... see what's happening.

PM sent and