Odometer not accurate

hello everyone. i got tacoma 98 2.4L and i’m having trouble with my truck’s odometer. i recently noticed my odometer is not accurate or it stops working at times. my work is 8 miles away from my house. and my odometer shows i drove only 6 miles or sometimes it shows only 4! the speedometer and everything else works fine. im not sure whats going on with it. and helps will be great! thanks.
(another unrelated question) is the ignition timing on this truck sets itself or do i have to get it checked manually? lately i’ve been having rough idle and weird rattling noise from engine)

 

Digital Cluster right?

Is your speedometer not accurate as well? Your truck could've been regeared at one point causing inaccurate readings.

 

That would be a massive regear to go from 8 to 4 miles, don't you think?

 

its not digital. i went under dashboard to check wiring but theres thousands of wires going all over. it works sometimes. but then it just stops randomly for couple miles and starts working again.
the speedometer works perfect. its accurate.

 

Need a new speedometer

 

so it would be speedometer miscalculating mileage even though it gives the right speed?

 

Odometer is part of the speedometer. It probably has a bad gear in it.

 

What wheel is that? Looks sick

 

Someone damaged the cluster when they pulled the air bag lightbulb. That's my 1st guess.

 

This would be my guess too - cracked gear or missing tooth. Maybe PO cracked it while "unwinding miles" - just saying.

 

You're right. Just throwing ideas out there.

 

The fact that you have a mechanical cluster makes it more prone to failure - more moving parts than a digital one. The mech. cluster is cable driven while the digital cluster uses an electronic VSS. As everyone above said you probably have some broken teeth on some gears in the cluster, 20 year old plastic and all.

 

The good news is that you can take apart the odometer mechanism and check for issues

 

That makes complete sense. i will take out the cluster and see if i can figure anything out. either way i might end up getting new one.

 

took out the cluster. the speedometer is not cable driven. does anyone have wiring diagram for this cluster?

 

Which owner are you? I'd check like a CarFax to make sure to mileage is correct. Who knows maybe the last owner rolled it back.

 

Your ODO is gear driven, and I'm guessing your speedo is too. Take out the speedo/odo mechanism and look for broken gears.

 

very first owner. my dad got it with 2 miles on it. he never worked on it.

 

Huh wow, that's cool. I would take apart the cluster and inspect the gears.

 

^x2