96 GT speedometer quit, OD light flashing

robg860

New Member
Mar 2, 2004
117
0
0
Hey,

this weekend my speedo quit only 1 day after my gears were installed. I lost overdrive with the speedo now sitting at zero all the time. I was told that it was a speed sensor and a pretty easy fix. My car is a 1996 GT.Does this sound right??? I thought it may be a coincidence and not gear related as it did work a full day. The check engine light and OD indicator light both flash now. Going to a tranny shop tommorrow to get it fixed hopefully. Anyone else had this issue????
 
  • Sponsors (?)


robg860 said:
Hey,

this weekend my speedo quit only 1 day after my gears were installed. I lost overdrive with the speedo now sitting at zero all the time. I was told that it was a speed sensor and a pretty easy fix. My car is a 1996 GT.Does this sound right??? I thought it may be a coincidence and not gear related as it did work a full day. The check engine light and OD indicator light both flash now. Going to a tranny shop tommorrow to get it fixed hopefully. Anyone else had this issue????


Sounds like a speed sensor all right. You still need to correct the speedo for the gear install, especially with the fully-electronic automatic 4r70w that's in that car. That tranny's shifts are competely controlled by the PCM via various sensor inputs, one major one being the speed sensor. If the speed sensor is inputing an incorrect signal because of the gear swap without the proper speedo gear being installed it will cause incorrect shift timing and various other driveability problems.

Get the code ran (that's why your O/D light flashes) and get the correct speedo gear installed.
 
the speedo gear was installed, at the time of the gear change and seemed to read maybe a little bit fast from my initial impressions. Will installing a new speed sensor fix it. The first 3 gears still shift true to form, I just have no OD.
 
The gear doesn't give you an acurate speedo reading. You would be better to get a speedcal as soon as you can. Or have a chip installed to fix it.

I'm not sure if the code reader will tell you which speed sensor may be bad if that is the problem but give it a try.
 
My speedometer quit and my OD light flashed when i hooked the DM speedcal up. Then my CEL came on and showed VSS malfunction. Everything was hooked up correctly to. What's up with that? Bad speedcal or connection?

I still could use OD with it flashing
 
Steeda told me that changing the speedo gear in a automatic trans will not last due to the fact that the size difference and angles of the new gear and he also said it wont be accurate if gears larger than 3.55 are used
 
subscribing, i dont want this problem when i install my gears in the spring. Would it be better to get a chip or a speedcal? Which will solve the problem in a 96-98 auto?
 
rebelleader:

Pardon if my post sounded terse. The auto trans can't be fixed "externally" since it is completely controlled by the PCM. So, adjustments to shift and lock/unlock points can only be made via the tune. That's why I referred you back to your tuner.

Let us know how you make out with this.

Chris