90 S13 - Speedometer reads MPH - Car not moving - Odometer issues also!

[Peabody]

Hello, I am the original owner of my 90 S-13 with a 5 speed.

The Story of the Speedometer/Odometer issues. Around 1995 my odometer wound not advance sometimes when I would start the car. This would bug me on Vacations because I always checked my mileage. I would tap on the cover and after a few taps the odometer would move a 1/2 mile or 2 miles and then would not move so I would tap it more and more and then if would be OK for a few days or weeks. The Speedometer would always read MPH ALL THE TIME, it was just the Odometer that would act up. I drove like this for years with it acting up usually on cold days or when I did not drive for a few days. Maybe 5 years ago on 1st start up the speedometer would read 85% less then the real speed. I would be at 70 and it would read 15 and then it would catch up to the correct mileage and be OK. This would happen with the odometer working and without it working.

I still just live with these issues. About 3 months ago I noticed the Speedometer would be a little bouncy under 10 MPH and now if I am stopped the MPH would say 5-15 MPH and go higher & higher if I would rev the motor, as the tach would go up the MPH would also to about 45 MPH not moving.

This leads me to my high idle problems (would not go under 1500 RPM). I Changed TPS, cleaned ICU & nothing would work. The only way to get it to go down to 800 RPM's was to put the TPS at .10 volts and not the .44-.54 it should be set at. Then I would move it in the correct position and it was OK for a little while. Well now when it has a high idle I disconnect the Speed Sensor and it drops to 750 RPM's and idles much smother. I had a mechanic look at it when I had a poor idle and he changed the injectors which did improve the idle but it was not steady (would go from 750 to 900 then back to 650 then climb higher).

I remember reading on the site YEARS ago how to fix speedometer issues but cannot find it. Should I just replace the speed sensor or could the problem be in the connection behind the Speedometer?

I have a ruptured disc and cannot work on my car so I have to pay someone to do it but I just do not want to change parts that might not need to be changed. My neighbor said he can change out the speed sensor for me. Should I try that 1st and then look into the dash if the problem exists?

THANKS

S O R R Y S O L O N G
Modified by Peabody at 4:58 AM 2/2/2010

[Peabody]

Anybody?

[Sijonda]

Bump. You still have this issue?

I'm having a similar issue with my 91 240. My Odometer is fine but my speedometer likes to either read 0 mph, bounce around like when I'm driving 65 ish, and once it actually topped out past 115. It did this with the KA and is still doing it with the SR I swapped in so I know it isn't in the wiring harness off of the ECU or the engine. and the transmission can't be it either since my transmission was with the SR.

Guess that would narrow it down for you. right now I have my cluster hanging out since I wanted to check it umm.. disconnect something .

I'll let you know what I find.

[kouki-guy]

I have the same problem. My speedometer doesn't ever read correctly, however I know at 3000rpm I'm ~70mph (confirmed with a gps) so I use my tach as my speedo (2600-3000 4th = ~45mph, or 2000 5th = ~45mph). Anyway my odometer would run while the car was idle and not moving. I figured it would be my speed sensor, however with the speedo AND odometer problems, I'm thinking its the cluster.

To affirm even more suspicion that its the cluster, my cruise control died randomly and ultimate doesn't work anymore. (It's not clutch switch btw).

Also there is buzzing at idle from the cluster, leading me to conclude that a host of electrical problems in the cluster could be the cause.I am at the moment looking for another sohc cluster to test.