My Speedo jumps around at times, almost never displaying the proper speed. I have replaced the speedo sensor and don't know what else to do. Help!!!

I own a 2000 Z28, w/6 on the floor

 

that's probably a problem with the instrument cluster. I know the 04 Monte Carlo had that problem and evidentally there was a recall on that for my Monte Carlo for that so luckily it was able to be replaced for free. But my money is on the cluster. Check for recalls first though.

 

How about. what year is the car? I have an 84 camaro. Stock speedo would jump all over an be useless... replaced the cluster with a digital cluster, and electronic sending unit. it STILL jumps around all over. replaced the driven gear, still does it.... the drive guear looks flawless... So... What could the problem be then?

Figure i would edit and mention mine is aftermarket now.. So a loose ground may cause it yet? would be nice if all of them may be that

 

Sometimes a loose ground will do this.

 

Info on the year/model would hep, if you add that in to your signature more people will be able to help you better....

If this is on a 4th gen, your either looking at a ground problem like the previous posted said or your ignition switch is getting ready to go out on ya. The Electrical switch about half-way down the column. Try wiggling your key a little when it starts acting up and see if it stops bouncing around or if the car cuts off altogether. ***obviously do this going very slowly on an empty street or parking lot*** Mine did this the first time the switch went out and I ended up driving home holding the key between run and start....... After the third switch, I went to the salvage yard and got a new pigtail for the switch plugs. Problem solved. Loose or corroded plugs on the switch will cause the switch to burn up.


If you figure out which it is, and need help, just ask. Either I or someone else on here can walk you through it.