Autometer Elite / Stack Pro Control Problem

I installed a Stack 3508 Pro Control water temperature gauge last weekend and its been driving me insane. 

No matter what the gauge stays at 120 degrees. You turn on the car and it will reset to min (100) and then will go to 120 and stay there. 

I checked the wiring and it has continuity from the sensor to the gauge itself. 

I am afraid it could be some setting on the gauge is not properly set, but I have no clue what. Anyone has any ideas? 

I would pull the sensor and place it in boiling water but I want to check everything before I go through the pain in the but that is removing it and removing all air from the cooling system. 

Its a 1/8-27 NPT threaded sensor and Teflon tape was used. I read somewhere that there is a possibility the sensor is not grounding properly. Would checking resistance between the sensor and head or a ground tell me if that is correct?

Also, I have been trying to reach Autometer for the last three days by phone and email. Covid is becoming a scapegoat for crappy customer service lately. 

No help from them. 

Bumping this in case not everyone saw it and someone can help out. 

Checking resistance seems like a good idea. If your meter is toast, jumper cable the sensor to ground and see if that helps.

In reply to matthewmcl (Forum Supporter) :

Finally after exactly 1 week I got a call from Autometer. Insane. 

This is what they have instructed me to do:

1. Disconnect the harness from the sensor and bridge the wires. It should peg the gauge at max. 

2. As temperature goes up, resistance decreases. So if I want to remove the sensor and check it, warm it up and check the resistance. 

We'll see where this gets me. Probably to a new set of gauges. 

FYI in case anyone cares. The PN for the replacement sensor is 2252.

If you think the teflon tape is a problem, yes, you can ground the threaded nut separately and see if that works.

I have the same gauges and I love mine.

Did you set your low/peak/warning?

It shouldn't matter, but wondering if those settings (or lack thereof) are messing with the gauge/output.

I agree, sounds like a input (sensor), but could be the gauge it self.  Which would suck (gauge issue, no sensor).

In reply to RACEC4R :

I only installed the water temp gauge and set the max temperature setting so that it grounds the electric fan and turns it on. Its one of the reason I went with these gauges as they have high low outputs that you can use to turn on fans or light up warning lights (oil pressure in my case).  

Fixed. 

So, just in case it happens to anyone else this is what I did. 

I disconnected the sensor and jumped the wires. Gauge pegged. 

I took a different sensor from the oil temp gauge and plugged. Same thing even when I heated it with a heat gun. 



As I was about to remove the extra sensor my wife told me the needle moved. It ended up being the plug not making proper contact. Not sure if the connectors are bent or what, but when I force the connector one way it works. 

Tonight I am going to try and straighten the pins in the connector as best as I can. 

Success!! It nows goes to min, so that means it works. Total pita to straighten the pins with the harness in the engine bay.