Tachometers provide a wealth of information much deeper than simply how many rotations the engine makes every minute. A tachometer can help to identify an engine cylinder which is misfiring, provide information on what the best gas to use for your S-10 is, and how much strain is being put on the engine under load, such as when towing a trailer or traveling on the highway. The trick is to be able to interpret the information. Installing a tachometer on your S-10 can help prevent serious repair issues, however.
Install the tachometer onto the truck's dashboard where you would like for it to be positioned. Avoid placing it directly in your line of sight, but rather place it to the left or right of the steering wheel, where you can see it from the corner of your eye. The tachometer kit includes a mounting bracket with self-tapping screws. Screw the mounting bracket onto the dashboard and mount the tachometer onto the bracket.
Run the wires for the tachometer behind and below the dashboard and out through the firewall. There are several other wiring harnesses along the firewall of the S-10 with rubber seals. Push the wires through the seals and into the engine compartment.
Open the hood of the truck and pull the wires through. There are two black ground wires and two red power wires included with the tachometer. Bolt the ground wires together on a clean, unpainted chassis ground, then disconnect the battery of the truck.
Open the fuse box of the truck, then unbolt it from the frame to provide you access to the underside. Locate the fuse which powers the ignition circuit, and insert one of the red wires into this slot. When complete, bolt the fuse box back to the frame and replace it's cover.
Locate the truck's distributor. There is one wire leading from the distributor which can be used for the tachometer. Following the tachometer instructions, splice the tachometer wire into the distributor.
