1993 S-10 Problems

[Shlimplisket]

I just bought a 93 s-10 and when i took it for a test drive, everything worked, guages and all. Now, two days later, the speedometer doesnt work, the voltage guage goes way WAY up, the fuel guage changes randomly, and just today, it decided not to start. I ran the battery down trying to get it started. Does anybody know how i can fix some of these problems? Please help.

[themodelkid]

welll A. your speedo cable could have rotted out and broke, take a look at it, it connects to your tranny on the side, you should figur it out, B. you prolly do have a bad battery if you ran it down trying to start it, lol. C. I'm not too sure bout the volt meter or your gas gauge, you could have some screwy wires, i have never had that problem so i cant really help u there, but i hope those other sugestions help you out! Good luck!

[themodelkid]

..... or you (the worst) you could have a bad computer in your truck witch would cause all the problems except the speedo, but i dout it.

[4onFloor]

did any of your lights get brighter when the volt guage read high? if so, it could have been your voltage regulator. And with that kind of spike it could have damaged other stuff as well. I have never torn into the dash on a 93, but as far as your speedo goes, it may not have a speedo cable, some GM's use a VSS (vehicle speed sensor) on the side of the tranny to send signals to the ECM to calculate vehicle speed, and the voltage spike could have damaged it. Just guessin.

[350 s-10]

i got a 92 s-10 and the guages on mine like the temp guage when you start it up the needle shots right up to and so does the oil temp 80 and it stays there also the battery does 2 is it just a fuse or what is it

[s10frameoff1993]

I have a 93 S-10 and the Vehicle Speed Sensor is plugged into the side of the transmission. there is no cable. Later.
-Chris

[94S-10/4x4]

I have a 94 s-10, does anyone know if it has an electric or cable speedo

[STOVE BOLT]

Originally Posted by s10frameoff1993

I have a 93 S-10 and the Vehicle Speed Sensor is plugged into the side of the transmission. there is no cable. Later.
-Chris

YEP.. CHRIS IS RIGHT. I HAVE A 93 S-10, AND IT HAS NO SPEEDO CABLE. IN MY OPINION, YOUR ECM WENT SOUTH.

[BlazerLT]

This has nothing to do with the no start condition.

Who cares about the dash working when the truck won't start up.

Have you:

Checked the battery?
Checked all the wires and cap and rotor?
Have you checked for a bad CPI injector in the upper plenum?

[STOVE BOLT]

If The Speedo Is Gettin Kinda Funky, Or Has Quit, It Definatly Is The Computer. It Is An Electronic Speedometer. Nothing Else Controls It But, The Computer. Combined With The Other Problems, That He Explained, I`ll Bet The Ecm Is Bad.

[Mikado14]

Let's look at what the poster of this thread has said.

First- he says that the voltage on the voltmeter goes way, WAY up. Two things can cause this, A bad regulator or a bad battery. If the specific gravity of the battery is low, like 1100, that battery will act like a high resistance to the alternator and the voltage could go as high as 16 V. Seeing has it is a used vehicle, maybe the seller put a surface charge on the battery and it only lasted for 2 days. Have the battery checked.

This same problem could cause erratic operation of the fuel guage, the VSS or any other electrically operated device due to the fluctuating voltage. The ECM should more than be able to handle the fluctuations since the CPU in the ECM utilizes 5V TTL circuits and I believe 12V CMOS and there are internal regulators in the ECM to prevent overvoltage.

Check the battery!

[BlazerLT]

Or, how about considering a bad digital dash as the overall problem.

[1999bravada]

Originally Posted by 94S-10/4x4

I have a 94 s-10, does anyone know if it has an electric or cable speedo

For 1993 you should have an electric vehicle speed sensor instead of a mechanical speedo cable.

Also if you have an automatic transmission, in 1993 GM started controlling the transmission shifts electronically.

[1999bravada]

Originally Posted by STOVE BOLT

If The Speedo Is Gettin Kinda Funky, Or Has Quit, It Definatly Is The Computer. It Is An Electronic Speedometer. Nothing Else Controls It But, The Computer. Combined With The Other Problems, That He Explained, I`ll Bet The Ecm Is Bad.

This is not necessarily true, but most certainly a definite possibility... I have a 1993 G Van which has the same auto transmission as the s-10 series and a 4.3L engine, but no digital dash. The signal from the VSS goes to a vehicle speed sensor buffer box before it reaches the speedometer and ECM. The buffer is a little white box with a circuit board in it just under the dash on driver's side and it takes the signal from the VSS and changes it to tell the computer what size tires the vehicle came with from factory, etc to regulate the speedometer output. I'm assuming this should be true as well for a digital dash, but with his other problems this has to be something either in the dash or the ECM as you surmised.

Also, to the original poster, you may want to check your grounds in the dash.. my analog dash on 1999 Bravada cuts on and off sometimes due to a bad ground somewhere in the instrument cluster.

[OtisvilleBill]

I was having the exact issues you were, and intermittently. I DID notice that it would happen after going over bumps, at times, so I concluded that something was grounding out/moving.
Long story short- my positive battery cable, going to the starter had made contact with the exhaust manifold, melted and the thing was grounding out at times.
It caused the dash lights to flicker, my gas gauge and speedo to act erratically, etc...
Check your wiring and save a lot of money.
Bill