I was hoping some one could shed some light on this for me. I am thinking of replacing my gauges with the Dakota digital vex gages, but was wondering about the speed signal that goes to the ECM. The gauges provide two switchable signals ( 2,000 ppm and 4,000 ppm) which one would be the correct signal that the ECM needs to see?

 

If this is tpi maf the signal is 2k ppm optical. If your using a thirdgen 700r4 there would be a buffer inline that changes the magnetic to optical 2k and 4k out.
If you want to change your options you can install a Dakota digital sgi-5

 

Yes, it is the maf TPI with the 700r4. So, the signal that enters the ecm needs to be 2000 ppm? Me current speedo is broke, and i noticed a decrease in fuel economy. I guess the torque converter isn't locking up.

 

 

Lack of a VSS input to the ECM can cause other problems


https://www.thirdgen.org/forums/post...740-post4.html

 

-Tuned Performance-, thanks for the diagram! My speed sensor is on the back of the speedometer, since I have a mechanical speedometer. Did the 88 and or 89 camaro or firebirds have the vss buffer module?

- Vetteoz- I am experiencing number 4 on that list. I was starting to think my Throttle position sensor was going bad, but I was going to wait for when I ordered the 'apu1' to data log, before I started throwing parts at it. I may also be experiencing number 1, but I am not sure if my tach is correct, and since no data logging yet, I have no idea of the true RPM

 

Since you have a mechanical drive optical vss in the speedometer. You will need to get this to send the vss signal to the ecm and a cable drive vss unit for the Dakota unless it accepts a optical 2k signal.
http://tpiparts.net/inc/sdetail/7586

 

Or you can use a Dakota digital sgi-5 with a 4k ppm vss to have more output options.
http://tpiparts.net/inc/sdetail/7587
http://www.summitracing.com/parts/dak-sgi-5

 

I may have to get the ski-5 to split the signal to also feed the cruise control, because I may also get the Dakota digital cruise control. The Dakota gauges will already come with the mechanical too electric conversion deal, to attach to the transmission. So, no more mechanical speedometer! My biggest concern was what signal the ecm needed to the it. The Dakota gauges has a selectable speed output for cruise or ecm, but it puts out 2000ppm or 4000ppm, that is switchable between the two.

 

I'm using this adapter for my intellitronix. I was told this sends a square wave signal to their gauge cluster and it works. But my car no longer sees a vss signal and throws a code 24. How can I make the car see this signal again. Can I split this signal between the guages and ECM. If so when can I tap the signal into at the ECM or hopefully behind the gauge cluster at the factory harness. Or do I need a different module to do so. Mine is a 89 iroc 5.0 automatic trans tpi. And my car does not connect to scanners due to baud rate or whatever it does that it dosent do.

 

I don't see the listing the output of that sender. you can allways call and ask there tech support. If you can't get a 2k ppm optical signal from the speedometer instal this before the inteltronix sender. Ground one side and the other side goes to pin A10 of your ecm.
http://www.tpiparts.net/inc/sdetail/7586

 

Btw your ecm will not start data flow until a to b on the aldl is jumpered with a 10k resister.

 

Ok I'll do the added sensor for the speed sense. I was thinking that also just wasn't sure where to send the signal to thanks. As far as the data at diagnostic port I can just add that resistor and my scanner will read the data. I got the solus ultra I'll try this in the morning thanks again.

 

If you are able to get a connection and the 1227165 is a pita and isn't the most user friendly ecm disconnect the 10k resister. If you leave in the resister the idle speed is commanded up and knock retard is disabled. DO NOT Drive with the resister in.

 

 

So at the ecm pin A10 what pulse does that accept. I ordered the dakota digital God-50 and was reading the instructions the lowest it goes it 4ppm will this work or am I asking for priblems?

 

Hope this could help
Best of luck!

 

And this too!
I have a brand new SGI-5 laying around that I have never used if interested

 

Does anyone know if running at 4ppm is a bad thing? I know I shouldent be driving without any vss but Iv been doing it for about a year and all I really noticed was fouled plugs after abouy every 6 months.