I am running a 98 LS1 in a 97 TJ
4L60e Trans
Np241c Drivers drop T-case (1988) With a JB conversions Super Short SYE

My engine harness was purchased from Howell Engine Developments.

The problem I am having, is the pigtail on my Howell harnes for the VSS has a 4 prong female connector.

The VSS on my 241 (Screwed into the output shaft housing) only has 2 male prong's

I obviously cannont plug in the 4 prong connector from the harness to the 2 prong VSS.

Who has run into this issue? Is there any way to adapt the 4 prong connector on my harness to the 2 prong VSS? and send the correct signal to the LS1 Computer?

I have had some mixed information from Advance Adapters, Howell & JB. Dont get me wrong they were all very helpful but in the end I still do not know exactly what to do.

I've got answers like, you may be dead in the water, you can just cut the connector on the harnes and hard wire it to the VSS, Your going to have to rig up a sensing location on the drive shaft, The signal that your two prong sensor gives out is different than the signal your computer needs (needs the 4 wire connection)

I was hoping to take a test drive next week, and im sure it will probably at least go into first gear without the VSS plugged in for a quick slow test drive. Im just trying to get all my ducks in a row, and get this fixed properly so my trans works/shifts correctly in 2wd, 4wd - Hi & Lo.

My computer has been flashed for the 4wd setup.

Any insight would be greatly appreciated. I can post pictures too if necessary, but I am sure that im not the first one who has ran into this. Thanks a ton.

I'd be giving Howell a hard time until they make it right. The VSS used on a '98 Camaro or Corvette (the only cars using the LS1) are also two wire sensors. Not saying they don't exist, but I haven't seen anything other than a 2 wire sensor on a GM drivetrain.

im going to call them again monday. sounds like all they can do is replace the whole dam harness. i wish there was a fast and easy fix for this. anyone else have a suggestion?

im going to call them again monday. sounds like all they can do is replace the whole dam harness. i wish there was a fast and easy fix for this. anyone else have a suggestion? If you new the pin out of the howell harness you could get a two wire connector and run it on the howell harness. Just have to splice and cut. But if I paid for a harness it should work!:mr-t:

But you need a 40 tooth VSS signal for the PCM this is the stock signal. Although, the PCM can use other signals if tuned to do so.

ya the jb super short kit came with a new tone wheel i believe its a 40 tooth

I have never seen a 4 wire VSS plug on a GM harness of any type, not even the LSx stuff. The last swap I did was an LQ4 6.0 into a FJ-40 with a stak t-case. The stak uses a jeep sensor, so this applies here.

First of all, are there actually just 4 wires? or just 4 pins? If there are only two wires you should be ok. In all actuality, you only need one of them in any situation. If you could get the pin out or wiring schematics from Howell, you should be able to fix it. I am unsure of which speed sensor you have... you said a 2 wire. What year is it? The later models with 3 wires use a sine wave signal, and the GM stuff is all square wave, and the 2 are NOT compatible without using a converter, but if you only have a 2 wire sensor, that should be a square wave too. If I am correct (and I think I am) you just need to ground one side of the jeep sensor, it doesn't matter which one. Then hook up the other wire to the high signal wire, as the low signal wire is basically just a ground. Now, if the ring doesn't have the correct number of teeth, you can have the computer tuned to read correctly, so its not a big deal. I would call Howell and ask them which wire is the Speed Sensor High Signal wire. If they can tell you that, you should be set.

Subscribed, Im doing almost the same thing....I know the 99-02 PCM only has two pins for the VSS. A reference and the signal pin 20 and 21. The Sensor on my 95 241C only has two pins. Im still trying to find a schematic for the 241C sensors because Im hoping to use the 4lo switch on the front as well.

I have never seen a 4 wire VSS plug on a GM harness of any type, not even the LSx stuff. The last swap I did was an LQ4 6.0 into a FJ-40 with a stak t-case. The stak uses a jeep sensor, so this applies here.

First of all, are there actually just 4 wires? or just 4 pins? If there are only two wires you should be ok. In all actuality, you only need one of them in any situation. If you could get the pin out or wiring schematics from Howell, you should be able to fix it. I am unsure of which speed sensor you have... you said a 2 wire. What year is it? The later models with 3 wires use a sine wave signal, and the GM stuff is all square wave, and the 2 are NOT compatible without using a converter, but if you only have a 2 wire sensor, that should be a square wave too. If I am correct (and I think I am) you just need to ground one side of the jeep sensor, it doesn't matter which one. Then hook up the other wire to the high signal wire, as the low signal wire is basically just a ground. Now, if the ring doesn't have the correct number of teeth, you can have the computer tuned to read correctly, so its not a big deal. I would call Howell and ask them which wire is the Speed Sensor High Signal wire. If they can tell you that, you should be set.


Thank you for the insight. I may be incorrect on the 4 wire statement, but i am almost positive the connector has 4 inputs. Im going to the jeep tonight after finals (school) to verify everything and take pictures. Hopefully it was just that the wrong connector was put on my harness and this is an easy fix. I will report back with the outcome. Again thanks for the help and clarification! Real good to hear that this "should" be an easy fix.

So I was incorrect about the 4 wires and the 4 female inputs on the pigtail.
It was hanging right next to the o2 sensor so I must have confussed the two.
:homer:

The VSS sensor connector off my harness is two wires, but the connector is too small, so I will need to replace it, or just directly wire it to the VSS.

Sorry for any confussion I may have caused.

I still havent verified if my trans is going to shift correctly. I will be doing that this weekend. Hopefully my tone wheel works out, and I dont need to re-tune the PCM.

So I bought a VSS for a 2000 Silverado. This VSS is a bigger diameter and does not fit in my JB Super Short Housing. Its basically the same style VSS, it accepts 2 wires, its just a larger diameter and the female portion is for a smaller pigtail connector.

As far as I know(and I could be wrong), this 2000 sensor sends out a different signal than the older one's, and It has the correct signal that my 2000 PCM is looking for, and should allow for my trans to shift correctly. As of now I only have 1st and 2nd (shifts hard up & down) with the old VSS which I believe is a 1988 sensor)

I have been told a 2000 VSS is what the 2000 PCM is working for, is this true?

Is there any way I will be able to make the older VSS work with my PCM?
Do I need some kind of signal converter box so the pcm recieves the right signal? or possibly my currently small 1988 VSS just needs to be replaced with say.. a 1998 sensor, the 1998 sensor is the smaller style too, (but maybe its different internally then the 1988...

Boring out the hole in the JB super short housing to accept the bigger VSS is not an option, because the housing is very shallow, and the small sensor right up agains the T-case, there's no way the bigger one's going to fit.

I bought a rebuilt trans, and reverse does not work, so I am pulling it, and trading the shop for a new one this weekend.
I would love to get the VSS issue figured out so I can have a drivable vehicle when I get the new trans back home.

Relly appreciate the help here...Hope nobody else is going through this...

For whatever reason, GM used a short harness that went from the plug in your harness to the VSS sensor. It was roughly 18" long. You could not plug the factory harness into the VSS without it. Napa should sell the proper connector for the VSS.

I've never read or heard of a change in GM's VSS. If you have a two wire sensor for your short housing, I would give it a try first.