88 22re, SR5.

The tach intermittantly acts up. Sometimes it dies and works it's way down to 0. In gear it usually works fine, but will sometimes jump around a few hundred RPMs.

Anything I can do other than install an aftermarket tach?

 

My aftermarket one does that.

 

Mine just started doing the exact same thing.

 

check the wires and connections on your ignition coil and make sure they're not corroded up or anything

 

Glad to know I'm not alone. If anyone finds any brilliant solutions, please let me know.

So the coil huh? Is that where the tach gets its signal? I was wondering just that. Exactly which connection is for the tach? I pulled the cluster out of the dash and cleaned all of the contact points and it didn't help, so it must be on the other end, just didn't know where. Thanks.

 

I've had this exact issue on all three of the Toyota's I've owned. My '90 3.0, my brother's '94 22re and my '98 3.4 T100. I've noticed that they all seem to do it when the temperature dips below 40. Other than that, I can't figure it out...

 

Well it's been 65+ here and it still does it.

 

Mine comes and goes. I have one of those cheap sun-pro ones from o-reileys. $35 tach, i guess i got what i payed for....

 

It was almost 80 here today and when it started to cool down some mine quit doing it, it just started doin it today and only when the cab was really hot.

 

I wish someone had a good fix for this problem! mine has been doing that for quite a while now, works fine, then drops to zero, then i hit a bump or it just magically starts working again. I do find that tapping on the cluster makes it work temporarily for a bit again.

 

Mine has a habit of at idle, reading nothing, and while moving, it jumps up about 500 RPM or so. Once you give the gauge cluster a good smack it jumps to its rightful area! at least its a religiously off tach in my case, but non the less, a bit annoying.

Try hitting it?

 

Mine does pretty much the same thing on my 95. I removed the coil (ignitor??) from the inner fender and cleaned all the connections very well but it didn't help at all. I'll just add it to the long list of electrical failures...

 

Mine does this too, I noticed it shortly after installing an aftermarket ignition.

 

as my brother(250000_yota) said earlier, my 94 22re tach usually reads high or jumps around when it's cold or raining. i don't know why, good to know that my brothe and i aren't alone. on a related note, my 98 3RZ tacoma does NOT do this at all, the tach stays true

 

Mine likes to sit at zero when idling...lol!

 

Mine just crapped out too. Worked fine, put in new engine with all new components including coil and igniter. Only thing bought used was distributor. New engine ran great till 3500 rpm then started cutting out and just bucking like crazy and the tach would jump all around. On last test drive, before I figured out the problem was the coil pickup in the distributor, I was cruising through town about 2k rpm and the tach started floating all over the place then finally just dropped to zero. Replace coil pickup and truck runs great now, but tach never recovered.

 

Nothing much to add, but mine does the same thing. At idle, it has an occasional tendency to sit below 500 rpms. At speed, it seems to be correct (or close enough).

It is an intermittent problem; and doesn't seem to be tied to temperature or atmospheric conditions.

I'd like to take apart an already broken one (that isn't in use) and see how they actually work. I'd bet they're electromagnetically driven, and that contacts are eroded or pitted.

Of course, as wires age they tend to become more resistant, so perhaps the tach wire from the ignitor just isn't getting enough signal to the tach.

But, then, as others have indicated, tapping on the cluster seems to get the needle moving again; even if not correctly.

Anybody have a shot gauge cluster (with a working tach) laying around that can be donated to Toyota science?

 

It's been many years and seems like noone has tried to solve the problem. Mine acted up yesterday, first time. At idle it was sitting at zero, but under any throttle it jumped to what seemed to be it's correct position. after a couple of miles it stared working normally.

Anyone fixed this issue yet?

 

These sure sound like wiring issues, so I doubt one fix would apply to everyone.

The tach signal comes from pin 4 of the ignitor, gr-r with auto, B with manual. You could check that connector for dirt and positive connection. That wire also goes to the data link connector (diagnostic port). Make sure you have the cap on the port so that you are not getting any electrical noise from damp/dirt.

 

I have an 82 pickup with the same tach problem so I'll be looking in to the connections. I also have problems with my factory temp, oil pressure, fuel, and voltage gauges. Sometimes they work, sometimes they don't. Is it cause from the same thing? Bad connections? Low resistance? Or do I have something else going on? I just replaced some burnt fuses and re-wired my tail lights. I'm hoping something I did wasn't the cause.