97' ka tach

[lego126]

Hey guys. I've got a 97 4x4 hardbody. I've had for 15+ years. Even when I first bought the truck the tach would jump around. I've. Searched and only thing I could find is about the dist. But nothing specific. I know its an electrical tach that's hooked to a resistor I think some where in the diet. But other than that I'm lost. I've never really minded it cause its always ran great but 3 years back I had the timing chain eat a hole thru water jacket in timing cover like so many ka owners, and ever since I've always wanted it to be fixed. Anyo e else experienced this problem. As always thank you for tour help!

[datzenmike]

I know the KA24E chain tensioner and guides are shit and should be replaced every 70K. The guides are plastic and they wear and fall off.  Tore down a KA24E and when I pulled the pan found this.....

 

 

Bet every KA out there has this. Without them the chain probably slaps around and hits the pump cavity?

[lego126]

So does.anyone know where the tach actually hooks to the dist?? My tach will never go below 1000. Even when turned off. Once over 1000 it will jump up and stop but its not smooth, its jumpy.

[datzenmike]

I doubt it does. The KA uses a CAS in place of a distributor. The signal generated goes to the ECU that 'sorts it all out' and determines what spark and the advance and then tells the coil to fire. I would imagine the tach is connected directly to the ECU.

[lego126]

Well snap! I was hoping it would be an easy fix. I'll have to check out my book and see if I can tea k it down.