car problem (odometer)

[porsche4786]

Ok, so I've got this problem with my odometer....(and yes I know this is a motorcycle forum but maybe somebody else has had the same thing happen).....

     Well today I got up and decided to see when the last time is I changed my oil. I walked to my car and grabbed my slip that i wrote it down on. It says 60,017 miles 10/22/1005 oil and filter change. I check my odometer and it says 60,099 miles today 5/6/06. I have driven more than 80 miles in the past 6 months. But probably not more than a few hundred. I know my speed is correct because my friend had a gps on him in the car last night and it showed my speed (i didn't know i had a problem last night) and it was right on. I drove it around today checking my trip with my odometer and it wasn't working at first. I probably drove 15 miles and it only went a couple miles. Then I stop at subway, get back in and drive and i notice it's now at 60,010 miles. Somehow a few more miles all of the sudden were on it...weird. So I drive for a while and my speed was accurate with other traffic, the trip was then matching the odometer after a while of driving. But now when the digits are changing they go half way pretty quickly, then stops in the middle between the numbers, then when the mile is about over (according to the trip) it goes the rest of the way right as that miles is done. Seems like it should be going smoothly the whole way with no stopping. Also, I drive the miles loop around my neighborhood and the trip and odometer both showed 1 mile.

Any thoughts on what the problem is? Maybe the speedo cable needs lubricating? I have 17 inch wheels with 215/45 tires, if that makes any difference.

[starwalt]

What year/make/model car is this?

Is this a digital or mechanical odometer?

If your car has an ECU (engine control computer) your speedo is most likely electronic, but it really depends on my first question.

More data is needed. Someone may have had the same experience.

[porsche4786]

1989 mazda rx7, mechanical odomter

[yamahonkawazuki]

aye perhaps in the drive at either end?

[porsche4786]

I'm confused because, the speedometer cable is what turns all of those things right? The speedometer, odometer, and the trip.  The speedometer works just fine with actual speeds. I guess it works now though, but it's like something got gummed up or stuck. The numbers still don't turn smoothly, they still go half way, then stop, then when you've gone a mile it turns the rest of the way.

[average]

idk, have you swapped cluster recently? Cable not totally connected 

[porsche4786]

No, I have not. The only recent mod is a short shifter (installed about 2 months ago), but I don't think that would have anything to do with it. Maybe the speedo/odometer cable popped out or something? But the speedo works so that's why I'm so confused.

[average]

Pull the cluster and see if there is something obstructing the mechanism like dirt or grime.