tach goes out intermittently

[his dudliness]

hey guys, New to the actual question asking, jus cuz I usually find what I need. this time I looked and can't find what I need.......so here's the deal, this is my second 60 and I've solved most of my major problems so far, but in doing so I noticed my tach works and then I look down and it won't be. I am interested in any and all suggestions....thanx y'all in advance!

 

[Slow Left]

This is a FJ60? What year?

Are the other gauges (volt, temp fuel) acting strange, too?

The tach gauge shares a common ground with those gauges (see wire diagram in the back of the "chasis_body_1980 repair manual" Factory Service Manual - below is an image grabbed from that diagram)

for downloading FSMs, go to:

https://forum.ih8mud.com/threads/fsms.743084/

 

[Slow Left]

Coil Test from the 2F Engine FSM (NOTE: read full procedure in FSM first before testing, this is done with the engine off):

 

[yarrie303]

my tach is doing the same thing. 84 FJ60. I will check the wires per this wiring diagram, any other advice? Per the post above its not the ground as all the other gauges are working & the gauge lights.


mark

 

[Dlathem]

You guys ever figure this out? Mine is doing the same thing. Not the ground because all other gauges work fine.

 

[LCnAZ]

See if this will help. It did for one of my gauges. The tach may be different.

Temp Sending Unit?

 

[maxbob002]

Mine went out intermittently when I first bought the fj. P.O. told me the coil checked out ok. He had bought a used tach but not installed. I installed it and it’s worked great since.

 

[Dlathem]

Good point. Could be the tach.