DaddyRunner

So my tachometer only works when it is cool out. If the temperature out side gets too warm like anything above 80 my tach sits there like a dead fish. But when it is cool it will just all of a sudden come to life. And actualy one time when it was hot and not working I had to get into traffic so a floored it the tach came to life jumping up and then when I let off the gas it died falling the other direction. Now when it is dead it points straight down and when it works it comes up against the pin.

I have a 95 4runner 3.0 liter sr5 5 speed. Nothing else is affected speedo and odometer work just fine. Thanks in advance and I tried to search but found nothing quite like this.

250000_yota

That's pretty much the exact opposite of what i've been dealing with. My tach gets kinda squirrely when it's cold, and tends to read 0 when the truck is idling, then it pick's up when I give it gas. I was thinking there might be some high resistance issue somewhere in the system, that when it's cold, get's accentuated. I haven't had a chance to really look into it, cause I work alot but if I figure mine out i'll post it up and hopefully can help you out a little.

toyospearo

I will be waiting to figure yours out because mine is acting up as well. If I figure it out I will post up the info.

250000_yota

Ya know the funny thing is I posted about this a couple of months ago and no-one seemed to notice or have a similar issue I might pull my truck in and pull the guage cluster and see what I can see at lunch...

DaddyRunner

Do the tach's run off a cable like the speedo or are the electronic running off like engine spark? Is the cluster easy to get to or is it a pull the whole dash sort of endeavor? I've done alot of mechanical work but electric I will admit is my weak point. The resistance thing sounds plausible to me but I was'nt sure about replacing just the tach or if it was an issue further down the line.

I don't like to replace parts for no reason.

White4Runner

That's what mine's doing as well. Tach reads zero at stop lights, etc but seems to read normally when I'm moving.

Let us know what you discover once you get a chance to dig into yours.

White4Runner

Any chance to diagnose?

From looking at my wiring diagram, it appears the tach is fired off the igniter. I'm guessing that if something was wrong with the igniter the vehicle wouldn't run. Since I'm getting signal to the tach, I'm guessing the wire(s) is good.

I think that leaves the instrument itself.