I HAVE CONVERTED MY 89 GTA TO SPEED DENSITY,AFTER I GOT IT RUNNING I FOUND I HAD NO SPEEDO.SIMPLE FIX,RE-PINNED ECM CONNECTOR WITH RED WIRE TO THE GRN/BLK WIRE THAT GOES TO SPEEDO ON MY 89,AND SPEEDO WORKED.NEXT DAY,I TAKE IT OUT AND NO SPEEDO.WHAT GIVES?! I AM PRETTY SURE I BOUGHT THE CORRECT VSS FOR MY 700R4.THE TRANS ALTHOUGH CAME OUT OF AN 88 BIRD,REAREND UNKNOWN AND MY 89 IS 3.27 POSI BORG/WARNER.ANY IDEAS OUT THERE?THANKS IN ADVANCE FOR ANY POSSIBLE HELP,AND SORRY IF MY ANSWER IS ALREADY ON HERE.I COULDN'T SEEM TO FIND IT IN MY SEARCHES.THANKS AGAIN,TIMMY

 

I too did the speed density conversion to my 87 IROC. So your speedo did work then quit? Did you happen to check the male / female connections on the cluster itself? Or at the vss?

I've had problems with both of my 3rd gens at those two locations. Simple fix possibly? Hope so.

W

 

SIMPLE FIX I HOPE.THIS PROJECT HAS BEEN JUST THAT,A PROJECT.DON'T KNOW WHAT ELSE TO DO,PLEASE HELP!!!!

 

Weird you mentioned that. I have a 89 RS which I put a 91 TPI fuel system in. My speedo was cable driven and my ECM needed a electrical signal for the TC to function. I found that painless had a adaptor to convert cable revolutions into electrical pulses. Just found the one I needed and installed it (needed a dent in the floor to clear) and everything works perfectly.

 

Your 89 OE speedo is electronic?

 

CHECKED ALL CONNECTIONS TODAY AND ARE ALL FINE,BUT STILL NO SPEEDO.IS IT POSSIBLE THAT I GOT A BAD VSS FROM AUTOPARTS STORE?

 

Turn your caps off please, reading your babble gives me a migraine.

87+ firebirds had VSS at the trannys..
where I believe camaros started at 90+

Try placing a resistor to the two vss wires and see if you get a reading.

 

Check the new vss with an ohm meter. If the loop is closed, the product is good.

Since you replaced the vss, did you get and install the correct one? What else have you changed in your conversion? The ecm?

In my maf to sd conversion I replaced the OE ecm with the ecm from the donar vehicle. Then used the donar vehicle's vin to get the correct vss.

 

I'M PRETTY SURE I GOT THE RIGHT VSS.VEHICLES VIN WASNT AN OPTION FOR ME CUZ THE TPI INTAKE ECM AND HARNESS I GOT FROM AJUNKYARD SEVERAL MONTHS AGO AND THE CAR IS NOW LONG GONE.I LOOKED UP RPO CODES FOR GTAS,AND GOT THE PART FOR A 91 W/700R4,AND 3;27 REAREND USING THE RPO CODE.ALTHOUGH I REUSED THE SPEEDO GEARS THAT WERE ORIGINALLY IN THE 700R4,WHICH CAME FROM AN88 WHICH IBELIEVE HAD 2;73 GEARS.THAT WOULD ONLY MAKE THE SPEEDO BE OFF A BIT WOULDN'T IT? I WILL TRY THE OHM METER CHECK AND SEE WHAT HAPPENS.I'M NOT SURE WHAT YOU'RE SAYING NELAPSE.WHAT KIND OF RESISTORS DO I NEED TO GET,AND DO I CUT THE WIRES AT VSS TO CONNECT THEM? THANKS ALL FOR THE HELP SO FAR,I HOPE I GET THIS FIGURED OUT SOON. TIM

 

Bro, I am not sure what you are saying either I cannot read all caps.

 

SORRY FOR ANY CONFUSION,I'M TALKING ABOUT YOUR REPLY ABOUT CONNECTING ARESISTOR TO THE VSS WIRES AND SEE IF I GET A READING. NOT SURE WHAT OR HOW TO DO THIS.SORRY AGAIN I'VE NEVER GOTTEN INTO ALL THIS ELECTRONIC STUFF THAT MUCH.

 

Too bad you don't have the donar car's vin code. That would have been a sure way to get the correct vss and part number from the GM parts dealer....

If by chance you have installed the incorrect vss, it may flutter the speedo and then again, the speedo may not work at all even though the part may test perfectly good.

Another suggestion to confirm in fact that you do have the correct part is to talk with the GM parts folks. Check their part number against the part you installed just to make sure.

 

THANKS FOR REPLYING WADEBRYANT.I HAVE TALKED TO LOCAL DEALERSHIPS AND THEY SAY THAT CAN'T GIVE ME ANY HELP W/O THE VIN.SO, MAYBE IF THERE IS ANYONE OUT THERE READING THIS AND HAPPENS TO HAVE A 90-92 FIREBIRD OR CAMARO WITH 305 TPI&700R4 W/3;27REAR COULD I PLEASE BORROW YOUR VIN?

 

I'll save you the trouble of x-checking and matching my donar vin to the vss that worked for me....plus a little more. Hope it helps.

My donar car was a 91 GTA Trans Am, 5.7 TPI (speed density), 700R4, 3.08 gears. With the vin number I purchased the correct vss to make my speedo work. The GM part number is 10456088.
Last year it retailed from GM for $79.18. Wholesale price was $55.43.

I also tried GM part number 10456089 since it came up as a possible match (and it was cheaper) but, it did not work.

I believe that there are three possible vss combos but, please dont quote me on that. But at least I've given you two of the three vss numbers that I know of and the one that worked for me. Kind of expensive to try and fail but, you might be stuck anyway.

You might want to check the number on the vss that you've installed. It's stamped in real small numbers on the outer ring just above or below the male wire connection. It'll probably be easier to remove it to read it unless you have the part receipt that has the information on it. (That's why I buy GM parts when I can. Small plug there...)

If you didnt swap rear ends, do you also need to know the correct driven gear for your speedo to read correctly (once it's back from the dead)?

By the way, if you need a brand new GM vss part # 10456089, let me know. It's collecting dust on my shelf.

 

OH MAN,THANK YOU SO MUCH.I AM GOING TO CHECK ON THOSE PART NUMBERS ASAP.ON THE SPEEDO DRIVE GEAR BIT,I DIDN'T CHANGE REARENDS I INSTALLED A TRANS FROM 88 BIRD THAT I THINK HAD 2;73 GEARS. I'M PRETTY SURE THE DRIVE GEAR IS RED 17 TOOTH.BUT I DON'T KNOW FOR SURE YET IF THIS IS RIGHT GEAR FOR MY 3;27 REAR.SO IF YOU HAVE THAT INFO YES I ALSO NEED THAT,(ONCE ITS BACK FROM THE DEAD).THANK YOU AGAIN,AND WILL POST AS SOON AS I FIGURE THIS ALL OUT.TIM

 

OK,its been over 1 year since i first posted this.A few things have changed since then. I have now pulled the digital dash hack job int. harness and replaced it with a 91 transam harness,the eng. harness is from a 90-92 tpi bird with no buffer box and the ecm is the correct 730 speed density.
I also have installed gm no. 10456088 speed sensor in my 700r4 trans.
Yet,I still to this day have no speedo!The cluster itself has also been changed so its not the speedo itself.
This is driving me absolutely insane!!! WTF! else could be wrong?

 

anyone??!!!

 

Well folks,I spent a couple days scratching my head and thinking of what could be wrong with my speedo!?
I had purchased a prom reprogramming chip from TPI Parts and had vats,egr,and other various changes for my setup.Today I found that for some reason I had them program it for a 2000ppm reading? DUH!
Anyway,talked with them today,and are going to get me fixed up correctly.
Another lesson learned!