Speedo not work

[97tahoess]

What's up guys. Im new here with a couple of questions? I just got my 97 Tahoe in a trade and the speedo is not working and the fuel hand keep moving back and froth between empty and 1/4 mark. Can anyone one help me out with this and thanks in advance for any help.

 

[SunlitComet]

can i ask if the mileage still accumulates? do you have a scanner to plug in to measure mph data thru the diagnostic link? is the gas gauge doing this while suv is sitting still for at least 30 seconds.

 

[McFizzl]

Id say bad speed sensor.

 

[Gzes]

Mine was wiring problems. A swapped steering column fixed that

 

[SunlitComet]

i hate to break it to you g but the speedo only problem does not run thru the steering column.

 

[Gzes]

Remember on the silvi when the speedo wouldnt work and was in limp mode. It was the wiring from the column. The po had messed up wiring whoch caused the problem

 

[SunlitComet]

true but the vss is tied directly to the pcm in 1997 units it does not travel thru the column it stay outside the cab. where on yours you were in limp mode cause of loss of power and that power supply is in the cab around and on the column connectors. he has yet to claim a limp mode type of problem.

 

[97tahoess]

Hey SunlitComet no the mileage is no accumulate. I don't have a scanner. As for the furl had its move back a forth while I'm driving. Could this be a bad sending unit? I need to get this fix ASAP.

 

[SunlitComet]

a waving gauge is normal when moving. in a 4 door tank at 1/8 to 3/8 full it is the worst.

if no scanner hope on the freeway and engage the cruise control. does it hold a steady speed? tap the brake and let the vehicle coast a bit then select accelerate on the cruise control stalk do it go back and maintain previous speed?

 

[97tahoess]

Hey sun finally got a chance to drive the Tahoe. The speedo will move to about 10 mpg but I was going 70 to 75. Could the vss be bad or maybe be something else?