I've been having a problem with my speedometer and odometer for over a year now (had some more serious car problems to solve first). When I first start the car, and for about 5-15 minutes of driving, the speedometer and odometer won't work. The speedo stays at 0 and the odometer doesn't move at all. Then after anywhere from 5-15 min. later, the speedo will jump up and start to work correctly and the odometer will start to work. It will then quit and bounce constantly for about 1-2 min., and then finally work normally until the car is shut off.

I know that the first question is, do you get a code 24 (VSS)? The answer is no, not lately. After I first bought the car the SES light would come on while the speedo wouldn't work, then the speedo would jump up and start working, and the SES light would go out. I haven't had this happen in over 10 months, yet the same problem exists.

Also, I have a scan tool, and the speedometer and the computer read exactly the same (when the speedo is on 0, the computer is seeing vehicle speed as 0, and when the speedo finally starts reading and working correctly, the computer sees the same).

Does anyone have any suggestions on what to do? I appreciate any help.

 

i think you have an electronic speedo in your car.
the first thing i would look at would be the speed sensor wiring down at the speed sensor on the trans, the insulation on the wiring starts to break down from age & oil & you wind up with the wires shorting together. if the wiring checks good, the next thing to check would be the speed sensor itself. im sure Trickster has posted up a trouble tree & diagram for checking this out, a search should turn it up.

 

Yes, I do have an electronic speedometer. I looked at the wiring to the sensor yesterday, and it appeared to be OK, but I'll check again. The connector was nice and tight on the VSS, too. I tried to find some service manual info from Trickster earlier, and came up with nothing, but I'll try again soon. Thanks for the help so far.

 

You have E-mail Benm109.

 

Thank you, yet again, Trickster! :hail:

 

theres a 99.99999% chance your VSS sensor is going out.

it comes loose, doesnt spin, you get no signal.. then after awhile (or really high speed) it grabs and works for a little while again.

its a pretty simple fix...


raise the car so you can get under it, if you can, raise the drivers side higher then the passenger side... if you have to lift it level, raise the back end. this is to minimze the chance of fluid coming out..

unplug the old VSS

take out the 10mm retaining bolt (or was it 8mm i forget, its been a couple years)
the sensor pulls out with some slight effort.. suction holds it in from coming out fast..
pull off the plastic gear from the old sensor.
place the gear on the new sensor, using ATF to lube it.
lube the Oring on the new sensor.

slip it back in, keeping the retaining tab over the bolt hole.

replace the bolt
plug in new VSS

and you're done. set the car down and go for a drive.

 

I just replaced the VSS sensor. and the speedo still does not work. any other ideas of what might be wrong? thanks.

 

Is there any way that you can hook your car up to a laptop or a scan tool? This will help you determine if the computer is seeing vehicle speed or not. For example, if it is reading vehicle speed, than something is wrong with your speedometer or the wiring to the speedo. Maybe Trickster can send you some service manual info, like he did with me.

Just for what it's worth, the VSS was not the source of my problem, either. I pretty sure I know the problem now, I'm just waiting for the part (VSS buffer, although TPI cars don't have them).

 

Hey, I don't have any scan stuff for a laptop but my cousin showed me how to check for codes and we only got a 12 and a 13. 12 is supposed to be ok and 13 is for an o2 sensor but I don't have the sensors on the cats so that is not a probelm because the previous owner burned a custom prom. But we didn't get a 24 for vss so were not sure what is wrong.

 

Yours has a VSS buffer box mounted near the ECM on the passenger side.

 

camaro05, which car are you referring to? I assumed you were talking about your 91 Z, but you have a 92 RS listed in your profile, too?

 

Yes the 91 Z

 

hey guys, can you give me something to check next? or should I tear into the dash and see if the speedo wires came loos or something? thanks