Temperature Sensor help (4EFTE)

[Wizzard]

Hi,

I am currently at the tail end of a conversion putting a 4EFTE into a mazda 121. Its been a lot of fun, and the engine is running great in the car. I am usually very good at this stuff, but I think I am too close to figure this problem out and need some educated guess work at what could be happening.

The temperature sensor that goes to the dash is not working properly. Both sensors from both engines, just make the dash temp guage rocket to the top on start up. I am confused because I have tried both sensors from both motors (but will put the mazda one in because the sensor only goes to the dash) and they both do the same thing. I also have tried two different mazda 121 dashes with same result, and I have also tried wiring straight from sensor to dash, which rules out a short in the loom.

So I am confused, the only thing I can think of that could be wrong could be earthing? All the earths are connected (and as stated engine runs well) but I can't think of what else it could be.

Suggestions?

[dumbass]

Toyota temp gauges earth on block not sure with Mazda ones
Might be similar best get some 121 dash digs
Find the dash temp gauge wire and put a variable resistor on the wire and to ground
Then go up or down on resistance to see if gauge works ok and gradually goes up and down
This way u will know if it's wiring or gauge or sender

[Wizzard]

All sorted, its the grounding. Just dug up the wiring layout and noted where I have cut off the sensor ground. Thank goodness another problem sorted.

[dumbass]

cool
so mazdas are like toyotas in temp sensor wiring