Here is my setup first off:

Black - Negative 12V
Red - Positive 12V
Green - Blue Wire coming off the Dizzy harness

Anyway it works now.. but it seems to be really low when i rev it it should be at 4500 but instead it shows about 1500 RPM

does anyone have any idea why its getting such a low reading?

 

BUMP

 

did you cut the wire in the back for use on a 4 cyl...

 

hmm i bought it used.. what should i try?

 

theres some small wire on the back of the tech meter..i believe you got to cut all of them ffor it to be use on a 4 cyl...

 

cut all wires on the back for 4 cylinder vehicles.

Otherwise it will read kinda what it is doing now.