MPG sweep gauge on cluster

[blk90e30]

So on the way home from work i noticed that the mpg gauge on the cluster was acting a little funny, when i would start to drive it would go to 0 as i let off the gas it would go to 15 back to 0 then on the freeway it would shoot up to 40 and as i would come to a stop it would stay there ? any info would be great

Is this connected to the tps?

thanks for the help

[dnguyen1963]

Check your SI board/batteries.

[blk90e30]

Everything was working perfectly yesterday, and this morning would they just die like that

[dnguyen1963]

The batteries are over 20 yrs old! Plus, the SI board has been known to have cracks in their solder joints.

[Gregs///M]

Tach, MPG, and temp are all powered by your 20+year old batteries. They need to be changed or it will get worse.