Speedo reaches 160 and tach reaches 8K+ when I start the motor

[32ValveRom]

Hey guys, this is sort of a new issue that my car started doing about a month ago. When I start the car the speedometer reaches past 160 mph and the tachometer flashes over 8k rpm. The fuel oil and everything reaches full for a second too then everything returns to normal after a second or so. I know some import cars do this but why has my 99 Cobra started this only recently?

 

[joshjwc9]

The battery is starting to go on you. It is the telltale sign that the cold cranking amps arent what they used to be.

Don't procrastinate before the battery dies on you!

 

[wmburns]

+1 on above. The guages will sweep anytime the power drops too low.

Also check the state of the battery. Is the top clean? Are the terminals clean and tight?

 

[32ValveRom]

Actually, I just checked the battery and it seemed pretty corroded. Thanks guys