Car: 1994 Honda Civic Ex
Engine: 1997 B20b
Transmission: 1997 Gsr hydro, VSS mounting tab was broken when I got it and had always worked more or less so I never replaced it.

So my speedometer and odometer have stopped working, used to take a few minutes of driving, get up to speed and speedo needle would spring up and both would start working now neither works.


I have changed:

Entire Cluster ( junkyard) - All other gauges work: RPM, Fuel, Temp as do the gauges in the original cluster

VSS: Tried known working VSS from single cam and swapped the gears (d-series gear on vss was about half the size)

Bought a VSS from a d-series and again swapped the gears




DMM Testing:

On the engine harness I tested the VSS plug and

With the ignition off the yellow/blue wire had continuity with chassis ground (so its the ground for the plug?)

With the ignition on (engine off) the yellow/white wire had 4.76V so ~5V the Yellow/Blue wire had 11.8V so ~12V and the black had 0V.



I'm at a loss for what to do..

Cliffs: Tach works but no odometer or speedometer changed VSS, odd results from DMM test.





Car also wont go past 3500 RPM but I think that may be a problem with the ecu and not a problem with the speedo not working.
CEL does not come on with VSS unplugged with ignition on

 

>>> Car won't go over 3000 RPM even with my foot on the gas.

 

I just had the exact same issue, did all the test and swapped sensors and cluster. I ended up having a corroded harness going to the VSS. Clean that and make sure to check the pin so it's nice and tight. My speedo is fixed and working great. Good luck and let us know how it goes.

 

[QUOTE=platinumg2;47986031] I ended up having a corroded harness going to the VSS. Clean that and make sure to check the pin so it's nice and tight. My speedo is fixed and working great. QUOTE]

same. my ls engine did this.

checked wires going into cluster

checked the vss by putting the car on jackstands and have a friend turn the wheels while using your voltage reader.

then i replaced the plug going into the vss on the harness and it fixed it, you can splice three wires into the harness about 1" above the clip, and connect all three of the stems individually on the vss and see if it works

basically i made my own clip to see if it worked

these are the female plugs i used

 

I depinned and sprayed the plug and wires with electrical cleaner, repinned wires, didnt have any buildup and didn't seem to help. Speedo has recorded 2 miles over 300ish miles

Engine still won't go over 3000RPM, immediate fuel cut back to around 2500RPM, havent been able to meet with the tuner for any ecu diagnosing

 

When the speedometer does work I can rev to at least 4k, but it will not work over 35mph. Its linear up to 35 but then oscillates from 20-40 mph and returns to zero at anything over 35mph. What gives?

 

Fixed: Bad thermostat grounds


For some reason I thought that I had checked the thermostat ground wires, turns out I didn't. Two of the four wires had torn free of the connector. Spliced in a new ring connector and she's back to full rpm range with an accurate speedometer and odometer