S14 vehicle speed sensor question

[jlmason]

I've got a 96 ka24de auto s14 that I had a cel for the vehicle speed sensor so I changed it. It has since started throwing the code again. The shop I had it at for other stuff said they thought it was due to an oil leak that has been there for a long time leaking on to the lower harness and causing this issue. What is your thought on this?

[Agamemnon]

Is it leaking oil and causing a fault in the sensor?

[jlmason]

Not anywhere on the sensor as that is at the back of the tranny.

[KiLLeR2001]

Was the gear cog for the speed sensor pink?

[jlmason]

No mine was tan if I remember correctly. It was the oem one.

[jlmason]

I've been told that 240's don't like aftermarket speed sensors and that I maybe needed an oem one.

[Agamemnon]

Not anywhere on the sensor as that is at the back of the tranny.
Oops. I misunderstood. I took it as gear oil was leaking through the sensor.

Break out the multimeter and start checking for continuity in your wire harness. Check that before spending anymore money.

[seagrasser]

OK, need more info

Is your ECU OBD1 or OBD2
Is your speedometer reading speed? is it reading correctly?
Did your speedometer read correctly before you changed the part?

Let us know

[jlmason]

96 is obd2
Speedo works fine and always has. It had the code when I bought the car and when I replaced the vss it went way for a bit and then started showing up again.

[Agamemnon]

Sounds like the signal from the combination meter to the ECU is open or shorted.

[seagrasser]

yep, speed sensor goes from tranny, to speedo, to ECU. Since it is an auto, the ECU uses the speed sensor to gauge shifting in the tranny.

Check your ECU harness. Also check the pin going to the harness. At the ECU it's pin 26 (yellow/green wire).

[jlmason]

Question. If the obd reader shows the speed on it that means the ecu is getting a signal. But if the vss (speed sensor is not putting out the exact voltage needed will the ecu/speedo still work but throw the p0500 engine code for a bad vss?

[jlmason]

If I can't figure it out soon I may just go 5 speed now instead of later. Being that my car is an abs car and I'm trying to do this on the cheap (as at a later date it's getting a motor swap) what drive shafts combo will work that is oem parts? I've only seen one s14 abs mt driveshaft for sale in a very long time of looking.

[Agamemnon]

Question. If the obd reader shows the speed on it that means the ecu is getting a signal. But if the vss (speed sensor is not putting out the exact voltage needed will the ecu/speedo still work but throw the p0500 engine code for a bad vss?
The ECU can still throw an error code if the voltage from the sensor has dropped to zero even for a slight second while driving. From your perspective, the speedo is working correctly, but the ECU sees and intermittent signal loss tripping the code. Typically this error code will show up after a few startups. That's why I think you are having a open/short between the pigtail coming out of the combination meter to the ECU.

If I can't figure it out soon I may just go 5 speed now instead of later. Being that my car is an abs car and I'm trying to do this on the cheap (as at a later date it's getting a motor swap) what drive shafts combo will work that is oem parts? I've only seen one s14 abs mt driveshaft for sale in a very long time of looking.
You only need the front half of the drivershaft that connects the trans to the center bearing. Leave the back half of the driveshaft alone.

[jlmason]

So we checked the wiring from the speedo to the ecu. It had continuity but we did notice that the pin had push way back into the connector. We pushed it back in and reset everything on the thought that maybe it was not seating good and that it was causing the issue. Finger crossed it works. If not I may be looking into the swap sooner than I thought.

[DETONATION666]

Relivent question.. Does anyone know the pinout for the S14 VSS? I have this figure shown here shows that pin#2 on the VSS goes to the RY wire that enters through the gauge cluster @ pin 28. Pin#1 On the VSS goes to the R wire which enters through the gauge cluster @pin 35.

But do we know what 1 and 2 actually do? Do they both send VSS information to the cluster or would one be just the VSS/clusters ground? I do not have a manual for my S14 and haven't been able to procure this information myself.

http://i66.photobucket.com/albums/h253/GSPEC666/image.jpg2.jpg (http://s66.photobucket.com/user/GSPEC666/media/image.jpg2.jpg.html)

[DETONATION666]

The reason why I personally need to know is that I am using a Dakota digital box for a swap and I am looking to wire it directly into the cluster rather than at a E19/202 plug.

There are a plethora of writeups about gauges and Dakota digital but no specific information on what each pin on this transmission does "from what I can find".

[jlmason]

Don't know but the one I was dealing with that went to the ecu was pin 29 on the gauge side to 26 on the ecu.

[jlmason]

Update.
Jumper and connector being pushed in all the way did not work. I've ordered another ecu and also an oem sensor to see if I can get this fixed. Also on a crap note, it threw a p1447 code for the same stupid part I replaced just this past week. Looks like I may possible have a vacuum hose leak somewhere. Bought some hose and will be replacing all that I can find. May go as far as to replace the cross er tube to the air filter with an aftermarket one.

[jlmason]

Updated...
Changed out the ecu and sensor and it threw the p0500 code again. I don't know where to go from here. The only thing I can think of that might be left is the stupid lower harness. Any other thoughts?

[jlmason]

If I was to do the 5spd swap the correct way using the lower harness and ecu from a 5spd will this get rid of the code?

[Agamemnon]

Nope. It's your wiring.

[jlmason]

I figured it's the lower harness that has the vss wiring in it. My thought is that a new one will cost me 270 cause I can't find a used one and at that price I'm over half way done with a 5spd swap. Will swapping the lower harness to the manual harness and using the 5spd ecu eliminate the issue or am I missing something else?

[Agamemnon]

You can't use the 5 speed lower harness on a car that was originally an automatic. The 5speed wiring just doesn't exist on your car. you must modify your existing auto lower harness.

Simply changing your transmission and ECU wont fix your issues if the wiring has loose terminals and/or breaks in the wiring.

Have tried a different gauge cluster by chance? The speedo may have some broken solder or loose connections that may not be sending signals to the ECU.

[jlmason]

Oh I did not know that. Everyone makes it seem like you just plug in a new lower harness. Don't have a spare to try. Trying to track down a used lower auto harness to try.

[jlmason]

Just a small update..
Replaced the tranny ecu that is on the drivers side of the car and that didn't fix it. Got a lower harness on the way. It's a last ditch effort to fix it. If not all the auto crap comes out and 5spd goes in. The. I wont have to worry about it.