coolant gauge always hot
Team Owner
Joined: Jul 2006
Posts: 22,198
Likes: 4,185
From: Kannapolis NC
You were probably thinking of the fuel gauge circuit which is exactly the opposite. 
The best way to keep this sorted...
When ohms is missing from a gauge, it always goes to what you want the most.
Temp gauge = cool
Fuel gauge = full
Oil pressure = maxed
Oil temp = cool.
and it's just the opposite for each gauge when they are grounded out.
Can the needles slip on the gauges... Highly unlikely. Gauges that appear inaccurate are usually this way from faulty input or they have been calibrated wrong since new.
The needles are press fit and they can be pretty hard to remove at times. We use a cocktail fork that has been specially bent to remove the small gauge needles. The only time we remove the needle is if we are replacing a face (really no need now since the cost of a new gauge is cheaper then the labor and the face) or if the gauge is just no accurate and needs to be re-set.
The best way to keep this sorted... When ohms is missing from a gauge, it always goes to what you want the most.
Temp gauge = cool
Fuel gauge = full
Oil pressure = maxed
Oil temp = cool.
and it's just the opposite for each gauge when they are grounded out.
Can the needles slip on the gauges... Highly unlikely. Gauges that appear inaccurate are usually this way from faulty input or they have been calibrated wrong since new.
The needles are press fit and they can be pretty hard to remove at times. We use a cocktail fork that has been specially bent to remove the small gauge needles. The only time we remove the needle is if we are replacing a face (really no need now since the cost of a new gauge is cheaper then the labor and the face) or if the gauge is just no accurate and needs to be re-set.
The reason I mentioned the needle slipping, I've seen a couple of cars that when the battery (or gauge when testing) was connected in reverse and the battery (voltage) needle pegged full counterclockwise, it made the gauge read negative all the time. The fact that his read hot, but went hotter when the key was turned on sounded like the gauge was working, but reading hot at rest with no power.
Last edited by 65GGvert; Mar 27, 2015 at 09:11 AM.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,853
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
hey everyone, I pulled the connector off of the sensor and the gauge stays where it is, the new gauge that I put in did come already in the hot position, im going by the picture that is on Wilcox website that shows exactly where my needle is sitting which says I have grounded ohms, with the key on or key off or running the needle does not change it always on hot and when you turn the key on the needle moves slightly, I will start checking the wiring and I will repost with anything I find
Willcox
Last edited by Willcox Corvette; Mar 27, 2015 at 12:44 PM.
Thread Starter
Intermediate
Joined: Oct 2014
Posts: 44
Likes: 0
So I pulled the center cluster out and with the cluster unplugged the connector for the signal wire is showing me ground with a power probe, also with the sensor unplugged the connector is showing me ground, the 2 signal wires are getting grounded from somewhere I just haven't got a chance to test the rest of the circuit yet but I'm hoping to sometime over the weekend, but I'm leaning toward that I might have ECM problem cause I believe the wiring from sensor and from the gauge both go to the ECM and don't meet each other anywhere else
Thread Starter
Intermediate
Joined: Oct 2014
Posts: 44
Likes: 0
Fixedd
So I found the problem with the coolant gauge, the ohm wire from the back of the gauge runs behind the fuse box and was pinched between the fuse box and a ground, I fixed the wire and gauge works perfect, in case anyone needs to know I went through all the wiring from the sensors and the sensor on top of the intake wires directly to the ecm and the wire from the gauge goes to a sensor on the side of the block
