ok i'm really getting annoyed with this....

So background, i did a T5 swap. Trans did not come with a VSS, nor do they make a VSS my car anymore. I just bought a VSS from jags that run,the 2000 PPM one, along with a new bullet sleeve and brown drive gear from PATC. Hooked it up to the car today, just drove it and speedo does not work. Then i though maybe i connected the wires wrong, so i reversed them and STILL the speedo doesn't work. The only thing that sticks out is the note that came with the VSS. It said the sensor is a new model that doesn't need a buffer box to work. so what does that mean? Can i just disconnect my buffer box and it will work??

WHAT DID I DO WRONG?????

 

sensor looks like this.

 

nobody knows??

Here's what the note that came with the VSS says:

"The VSS uses a Reed switch and does not require a buffer or a DRAC - it gives a signal directly to the ECM.

one lead is connected to ground (It doesn't matter which wire). This wire should be connected directly to an ECM ground.

The other lead (output or signal) is connected to the VSS input on the ECM. On some truck TBI engines, the shop manual will call this the DRAC but its the same as VSS. check with the appropriate service manual for the correct wire.

Diagnostic checks: If you are having problems with a code 24 (vehicle speed sensor) , to test the VSS for proper operation, connect an ohm-meter across the 2 wires . The resistance should change from less than 2 ohms to greater than 100,000 ohms, 2 times per revolution of the VSS."

 

You just posted today,... give these guys a chance to find your post. When someone can help - they usually do ! I don't know the answer to your problem but will say this;

The stock "VSS buffer" is designed top accept the electric (tranny mounted) VSS signal. It then splits that VSS signal and sends it to various places; namely the speedo, the ECM, and the Cruise @ 2k or 4K PPM.

In other words,............sending your new tranny mounted VSS signal to the ECM is not equal to as sending the new VSS signal to the Speedo/Cluster.

Again; I do not know the answer. I will make a suggestion; Why not send that new VSS signal to your factory VSS Buffer ?? Then all the "out" connections ( speedo, the ECM, and the Cruise) *might* already be in place and will be getting the proper calibration.


Good Luck !!!

 

Wrong VSS, you need a 4K PPM magnetic sensor wired to the original wires that go to the 4-out buffer box.

RBob.

 

Thanks guys for chiming in.

I got the wrong sensor? ok then there's a LOT of contradicting information out there. everything i read on here said that i needed a 2000 PPM sensor. Heck even JTR says it! The old VSS i had in my t5 swap trans was for a 91-92 car and was a 4000 ppm and it didn't read correctly. numbers kept bouncing all over.

 

so i need this one? 4000 ppm sine-wave AC.

 

Just ordered the 4PAC VSS. we'll see how this works when i get it next week. Keep you all posted.

 

(yours) The 2,000 PPM ECM VSS-in-trans third gen applications used the VSS buffer box to cut down the VSS signal to the correct speed & type of signal for the ECM.

The 2,000 PPM ECM cable third gen applications used VSS-in-speedometer to provide signal to cruise & ECM; no cut down needed.

The 4,000 PPM ECM apps. (SD TPI) were VSS-in-trans. applications and were able to use the same type & speed of signal for cruise, ECM and speedo.

It could be argued the JTR information could be worded differently, but their work is geared towards a powertrain swapping hobbyist. Fewer people care to wire their car exactly like a Pontiac third gen 86-92 4bbl/TBI/MAF TPI application, although it's a reliable, sensible setup.

 

Thanks for the insight, JMD. Fingers crossed, the new VSS coming works.

 

ok, the new, 4000 PPM VSS just came in the mail today. i'm going to cut off the connector that came with it so i can attach it to the car's harness. Does it matter which wire goes to which? The instructions say" Connect one wire to the "VSS high", and connect the other wire to the "VSS low". The wire polarity does not matter because the VSS puts out an AC signal." So i'm going to take that as it doesn't matter which wire goes to which.

 

 

I don't think it matters !?! I don't remember high vs. Low signal,..... I just remember that its the Yellow and the Purple wires leading from the tranny to the VSS Buffer.


You don't want to bypass the VSS Buffer because while the Cluster needs 4000PPM,...the Cruise and the ECM still both require 2KPPM, and the stock buffer is already splitting the 4KPPM signal to 2K for those devices so you want to keep the stock Buffer in place and splice the new VSS wires to it. ( use the same 2 wires that connected the stock electric VSS at the tranny to keep it simple.)

Wish I could see your reaction once your speedo starts working again !!

 

SUCCESS!!! IT WORKS!!! THANK YOU EVERYONE FOR THE HELP!!!

Now who's looking for a JTR 2000 PPM VSS? not even a mile on it!

 

Okay. Now where's the video of the top end speed run with video on the LIE?

 

ok one last question: where can i get a cap to cover the cable drive end of the VSS? I don't want crud getting in there.

 

Wish I would have found this earlier as I too bought the 2000 ppm first. After installing the 4K vss did you have any problems with stalling at idle or stop lights?