Temperature sender

[bc3j]

Not an electrical guy so a question. On the sender is a black ring, insulator I think. If the the gauge wire is touching that, would it affect the resistance reading?  My original connector is long gone and is currently attached with a ring terminal and nut. The ring terminal is touching the black insulator. My gauge always reads low. In the second picture a laser thermometer is 183* at the housing. Stock cooling system with a 26" radiator, shroud, clutch & 5 bladed fan, 195* Tsat. Never gets above that even in the summer. Guess I have a hard time believing the car is that efficient. I keep thinking the gauge is off, sender is bad, or the wire is messing with the reading, but the laser reading always backs up the gauge reading. Maybe I don't have a problem. Looking for any thoughts.

[RUNCHARGER]

No it should read fine attached like that.

[JS29]

If the wire was grounding the gauge would peg to the max.   

[dodj]

Ring terminal is not ideal, but good enough. The only problem I could see would be tightening down on the ring terminal so much that you squish the insulator until the ring terminal touches the body of the unit. Then it will do what JS29 said. If you figure it is always reading low, check/clean the connector along the pass. valve cover and the connection at the bulkhead connector. If those connections are dirty and or corroded it will affect how your gauge reads.

[YellowThumper]

If you use ring terminal then use 2 nuts. 1 below and 1 above to tighten contact by sandwiching it between them.
Not making good contact it would have more resistance and would read low.

[bc3j]

Is the OEM connector still available?

[JonH]

https://www.repairconnector.com/products/GM-Ford-Chrysler-Universal-Stud-Socket-Pigtail-.html

[bc3j]

Ordered. Thanks