I need help form someone smarter that me!

[DCBoy]

Good evening! I am having trouble with my 2004 Silverado 1500 Temp Gauge. I had the old alternator die on me today so I replace it with a new 145 amp unit (upgraded from the 105 amp). After installing the alt, I noticed that my temp gauge was reading 160F after 5-8 mins of 70 mph highway driving. I pulled over and checked under the hood to see if the truck was over heating but everything under the hood was fine. When I got back into the truck, I turned the key to the accessory position. The temp gauge moved and indicated 210F. When I stated the truck, the gauge went back to the 210F then went directly back to 160F.

Do you guys thing that this problem is in the sending unit or in the cluster? Is there a way to test the cluster to determine if it is the problem?

Thanks in advance for any help you can give!

[silverado_lover]

I don't know but the title of the thread :lol:

[DCBoy]

Hey, I can admit when I am stupid on something...lol! :whatever:

[AltEffOr]

if you have access to a scanner that does live data, i would plug it in and see if the coolant temp is actually changing, would rule it down to the sender, wire, or stepper motor.

[DCBoy]

Thanks for the advice, I need to find a scanner. And the darn thing started working this morning....

[drbizerk]

when you kill the engine the temp of the vehicle will increase because the water pump isnt moving water and the air is no longer being forced into the engine bay through the radiator (your at a stop....). When you started the truck back up the water starts to cool imediately. thats the theory i came up with anyway