Details:
Vehicle: 1993 LT1 F-Body - ECM with a four-pulse (4000 pulses per mile) sine-wave (A.C. current or alternating current)
- http://www.jagsthatrun.com/Pages/Spe...eedometer.html
Transmission: TH400 Transmission with VSS sensor 8655315 and 40 tooth reluctor 8655291
- http://para.noid.org/~lj/TH400/TH400.htm

Problem:

The damn speedo won't work The current behavior is that the speedometer will peg itself at 150mph. Every so often it will tick back to 120mph and then back to 150mph. I've tried A4 and M6 programs where both have had an altered the road speed constant via Tunercat with no luck. Having read though a series of posts I investigated the use of a Dakota Digital SGI-5A box. Having spoke to their tech support they said this box would correct the speedometer. The SGI-5A box has a keyed-on 12 volt source with the ground wire running to the chassis. The VSS sensor has two wires, yellow and purple. Splicing into the yellow wore for the signal, purple is supposed to be the sensor ground, the wire end coiming out of the sensor is used a signal in and the wire leading up to the ECM/engine compartment as signal out. This is how the tech at Dakota digital told me to wire. Without seeing results I tried it the other way, still no result.
I'd really like to hear form others who have done this conversion or any other possible solutions. Has anyone hooked up the SGI-5a differntly? I'm not to reassured in the tech at Dakota Digital, he didn't sound too sure of himself.
Thanks
Jon

 

In TC did ya try changing the the mag vss bit? I know for SD TPI cars it is under the switch table.

I'd try that without using the SGI box first.

Also do you have some kinda scan tool?

Kat

 

Here ya go..

Kat