i just installed a oil temp gauge and now it is pegged at 250 at idle! My water temp gauge reads a steady 180. is there some way that it is the gauge grounds ,i grounded the gauge light and the gauge at the same place .i am using the mazdatrix oil temp adaptor block. wtf

 

does it go pegged with the ignition on engine off? if so it is either a bad connector at the back of the gauge or a pinched wire or faulty sensor. you can ohm test the sensor and check resistance to ground in each of the signal wires with the sensor unplugged which should lead you to the problem.

 

thanks ,but i have no idea how to ohm test and check the ground !

 

Like Karack asked above, if the car is cold and the ignition is in the ON position and the engine not running does the gauge still peg? Sounds like you grounded the wrong wire.

 

If you got an autometer 2 1/16 electrical short sweep gauge,

If you are looking at the gauge from the back with the light bulb at the top.. the sender gets hooked to the screw on the lower left, the ground to the center and the ignition 12v to the on in the right.

If thats correct... do you have the wire thats attached to the sender BETWEEN the two nuts on the sender stud??????? the wire can't be touching the body of the sender.......it can only be touching the stud, else you'll get a ground fault to the engine block through the body of the sender!

Check out the sender, at the base of the threaded stud, you'll see an insulator that the first nut sits up against so that it doesn't make contact with the body of the sender.

Either that or there is a fault in the wire connected to the sender somewhere...