Tach not reading correctly and speedo gear

[disciplerocks]

My tach does not respond. It moves as the rpms go up, but its not correct. I already tried to swap it for another unit. Where does the tach get its signal from on a motor with a coil pack?

Also swapped in 3.73s. Currently have a black 20 tooth gear. What gear should I be looking for to correct my speedo for little 205 tires?

 

[adsm08]

Coil pack engines take the tach signal off the crank sensor.

We have calculators in the tech library to figure out speedo gears.

 

[disciplerocks]

You think the crank sensor is bad?

 

[adsm08]

Maybe, but doubtful. A bad crank sensor is more likely to make it not run.

What are we working on here, the B2 or the Ranger?

There is a difference in wiring between the 4 and 6 cyls, the ground pin is different for the different calibrations and having the wrong one in there will make it read wrong.

 

[disciplerocks]

The Ranger.

 

[disciplerocks]

I found a chart of different speedo gear colors and teeth over on explorerforum. I'm fairly certain it wasn't accurate to start with so this might be a guessing game.

Still wondering about the tach though.