Goofy tach and speedo ={

mistamontiel

New member
ST184 , 92 Celica GT-S

So my tach is very bouncy and typically when I'm cruising she'll drop dead 0 er somehow maybe not no more forgot my last ride

Well this makes me 3-2 rev match a pain in the ass er any of the rev matches total guess .. it's always like throttle input memorization

My speedo jumpy too .. almost always showing way too high

My mech say the speedo is still cable operated , no electric sensor ..

I've the lithatoyotaparts store site (THANKS Corey!) .. so what exactly must I key in ?
 

mx6er2587

New member
Tach is definitely going to be failing capacitors. Super easy fix. There's a couple threads on it if you search a bit. The speedo makes less sense. As you noted they are mechanical and shouldn't read high ever unless your running a different overall tire diameter. There could be some worn/stripped teeth at the adapter on the transmission that could make it "bouncy" though.
 

EvilStig

New member
my friend had this issue with her alltrac (before it later became my alltrac). I'll ask her about it, but as I recall there was a pickup gear in the transmission attached to a cable or something, and the gear was made of something soft and had worn out or something. Probably a common weak point.
 

FC Zach

Active member
Yes, the "driven gear" is a plastic gear pressed/bonded on a keyed metal shaft. If that gear breaks a tooth or the keyed end of the shaft breaks, something caused it and that is most likely a defective cable adapter although it could be a cable issue too. My cable adapter locked up due to bearing debris getting between gears which broke both the key and gear.

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mistamontiel

New member
Speedo is ok minor wobbly works more often than not!

Just having this my first stick/standard three pedal n box and the tach is shit only readable if hold the window switch is damning!
 

EvilStig

New member
mistamontiel":3pbokc8r said:
Speedo is ok minor wobbly works more often than not!

Just having this my first stick/standard three pedal n box and the tach is shit only readable if hold the window switch is damning!

speedo will probably get worse, in worst case stop working altogether like this one did... makes it hard to keep track of mileage and maintenance since the odometer is tied to it and will also stop working. No clue how many miles are on my car between when it broke and when it was fixed. Maybe 20k. Maybe 100k...
 
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