firehawk1724

ok i knew my speedometer wasnt working i assumed it was the speed sensor and had plans to change it but i noticed my odometer doesnt work either...my tach and other gauges work.. any help and/or ideas are appreciated

vetteoz

iTrader: (13)

Year model and engine type help

ASE doc

If your speedo isnt working due to the speed sensor, the odo isnt going to work either. The speedo and odo are together in the same unit and get their info from the speed sensor. The only way a odo would work with a speedo not working is if the actual speedo itself were broken.

firehawk1724

ok well i didnt know that lol...so is it safe to say that its most likely the speed sensor?

ASE doc

Yes. There is a test for the electronic speedo. As vetteoz said, I need to know what year, model engine and trans to help you with that.

onewheelf4

i could use a little help in this area also. i have a 87 irocz with the 5.7 tuned port engine and the speedo just suddenly stopped working. after driving for a little while the mil light comes on. just wondering where to start before i start pulling things apart on my own. thanks

JamesC

iTrader: (5)

Welcome to TGO. Since you have a mechanical speedo, the following link should provide the info you need:

https://www.thirdgen.org/forums/inte...eedo-woes.html

JamesC

onewheelf4

would that explain the mil coming on? I was searching on here how to pull codes but cant seem to find a clear explanation on which terminals to jump either, i keep finding mixed answers. A little more info would be great... sorry to be a pain.

firehawk1724

its an 89 trans am 5.7 tpi w/700r4

JamesC

iTrader: (5)

IIRC, the code would be 24, Vehicle Speed Sensor. A working speedo should fix the problem (assuming that wasn't an issue beforehand).

An 89 TA would have an electric speedo.

JamesC

firehawk1724

since my speedo is electric the likely culprit would be the sensor itself right?

ASE doc

Yes. Very likely culprit.

firehawk1724

is there a way to test it?

ASE doc

The proper method for testing the VSS is to use a scanner to read vehichle speed. The VSS produces an AC signal which the VSS buffer converts into digital pulses. It is possible to use a voltmeter to test for voltage at the VSS while running the car, in gear with the wheels lifted. PLEASE BE CAREFUL!! When doing this. Make sure the car is securely supported and stay away from the turning wheels.

Look for AC voltage at the sensor. If there is none, remove the VSS from the trans and spin it with your fingers while watching for AC voltage. If there is no signal when spinning the VSS, replace it. If you get a signal when spinning the VSS by hand, check the speedo drive gears on the sensor itself and on the output shaft of the trans.

This is another case where it really pays to have a scanner. A Snap On brick, which is an excellent scanner for the 3rd gen, can be had for as little as $300. I cant think of a better value for the price.

firehawk1724

who would sell the scanner? autozone perhaps?...also where the speed sensor is located on the trans it has a circular seal behind it right? its leaking trans fluid is that a easy fix? just undo the bolt(s) that retain it and pop seal out and replace or is it more involved?

onewheelf4

which terminals on the link dlc do i jump to make the light flash the code? thats the issue i was having trouble with. Thanks

ASE doc

The speed sensor is seled with a rubber o-ring. Just replace it with he same size o-ring. There are several scanners that will work on the 3rd gen. My favorite scanner for these older cars is the Snap On brick. They are available used on e-bay or from your local Snap On dealer. They run about $300. The 3rd gen is OBD1. It takes a GM OBDI interface adapter to connect to the 12 pin DLC. Make sure whatever scanner you buy has this connector.

To read codes, jump terminals A&B in the DLC. They are the two terminals in the upper right hand corner.

jreyes916

hey bro i just jumped mine its the two on the top right corner i used a safety pin i was worried id do it wrong but it worked if you need help let me know ill tell you how

jreyes916

how hard is it to remove the vss from an 89 camaro 700r4

JamesC

iTrader: (5)

The VSS on an 89 Camaro is located on the rear of the cluster.

JamesC

jreyes916

then what is the sensor and connecter at the tail of my trans i was told that was my vss

JamesC

iTrader: (5)

Cable connection or connection for back up lights.

JamesC

alexquade

iTrader: (2)

HEY! im having issues too!! Except, my speedo jumps. Itll bounce between all the dwn and the speed im doing. Well it used too. Nw, itll bounce a lil. And thats it. BUT! My gas gauge started wiggin out too. Like, About a week r two it was reading 1/4 of a tank fuller than it shldve been. Then went to normal. And about two days ago, it pegged ALL the way out. Went from almost empty, to past full, and hit the plastic gauge lay over. And my oil pressure gauge, sometimes itll read 30 psi higher than it shld. Like. Itll read 60 psi drivin and the line before 60 idle. When it normally reads 30 idle and the line before 60 idle....

P.S. Its a 92 camaro, 305 tbi, SHLD BE 700r4.

THANKS!

Edit!: ONLY that half of my dash cluster is wiggin out. My tach, temp, and volts never mess up. That i know of. Any advice is appreciated! Thanks!

Lmancha96

having the same problem with the speedo/tach/gas gauge

Speed/tach do not work at all. Tach guage is topped out and speedo guage reads 0mph all the time. This thread got a little confusing when one guy said the VSS was on the transmission & another said it was behind the cluster.

Which is it? & should my Cruise Control & Odometer be working if the speedsensor is out?

& is the VSS an abbrivation for vehicle speed sensor?

91 rs 305 tbi

JamesC

iTrader: (5)

On the backside of the cluster, 82-89. On the tailshaft, 90+.

Yes.

JamesC

Mancha87

Would the speed sensor also effect my acceleration? When I start the car up it revs itself up to about 2k rpms. I can't know for sure since the tachometer is'nt working but I can tell its revved.

Sometimes it's revved up the whole time I'm driving it so I'll be at a light with my foot on the brake and I can feel the car over accelerating. Other times it works normally.

1991 rs 305 TBI camaro