tach went dead

[durecell]

so ive had this problem since I got the car last spring. ill be driving along at high way speeds and the tachometer goes to 0 and stays there for awhile and then it comes back. hasn't done it ever driving in town. the car will drive fine and doesn't die. I pulled over the first time it happened and shut the car off and it started fine but with a dead tach. then after awhile it came back. haven't really worried about it. I just figured since I have access to this site with so many smart tercel lovers I would ask and see what I get.

my thoughts are the gauge it self or the printed circuit board on the back of the instrument cluster. I took it out and looked at it but it seems physically fine. I have a spare but didn't want to just swap the whole thing. I want to keep my mileage reading. think I might just change the tach gauge or the circuit board depending on what you all have to say. thx

[dlb]

i would swap your spare in and drive it at highway speeds just for a day or whatever to see if it is in fact something in the cluster. if that fixes it, i agree you could swap just the tach and/or the flexible circuit board. if it doesn't fix it, the problem is likely in the distributor. might be a dirty or marginal contact or something that can't pick up a signal past a certain rate.

[durecell]

hey thanks dlb. that's what I wanted a little input. appreciate it. if its in the distributor. do you know which wire is for the tach?

[dlb]

no, i'm not sure but IIRC the dizzy only has a single green plug so it must be in there. check the wiring schematic in the back of the FSM, it might have something useful in it.