The sender with one wire goes to the instrument cluster and drives the temperature meter.
The two-wire unit is part of the Engine Control Unit (ECU) sensor system.
Normally, someone might say something smart like "Your engine does not have a second sensor! What the heck are you taking about!!?!?"
Under normal conditions, an '88 Samurai has only one temperature sensor mounted below the thermostat housing and sports a Hitachi carburetor. However, what you are describing is normally found on a the intake of a 1.6 engine or possibly a throttle-body-injected (non-carbureted) 1.3.
It is quite possible that someone has replaced the 1.3 with a 1.6 or has swapped out the Hitachi carburetor for the newer throttle body Injection system with the corresponding intake and ECU/wiring harness.
My bet is that you have 1.6 engine! That would be a GOOD THING!
The quickest way to tell is to look at the rear edge of the block on the exhaust side of the engine where the transmission bellhousing is attached.
You will see "1324 CM" for an '88 Samurai 1.3 or "1596 CM" for a 1.6 8 ro 16-valve Tracker/Sidekick engine. It may also say 1298 CM (or therabouts), which is the newer version (1989 and newer) of the 1.3 Samurai engine.
In any event, There is only one temperature sender on an '88 Samurai, I know 'cause I own one.
There are 2 senders on a 1.6 engine - again - 'cause I own one.
I hope that this helps!
searchable links to the Samurai/TracKick
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