here is my problem when i start up my chevy 1500 hd with a 6.0 the rpms read 6000 rpm and wont return back to the acutal reading of the rpm but if i shut the truck off and start it 5 or 6 times it slowly brings it down so i was wondering what the problem is thanks

 

sounds like your tachometer might be stuck. it may need replacing

 

my tac works fine ill be driving around and it would be acting normal and then all of a sudden it would read 6 thousand rpm then i will shut the truck off and start it back up and it will read 5 if i keep doing that it will keep dropping it 5 thousand rmps at a time until it reads normal operation i hope you understand what im tryin to say here it may sound confussing thanks

 

Possibly a bad ground, or the stepper motor.

 

the bad ground is entirely possible, a friend of mine had an old Buick that the tach and speedometer werent working. He replaced the motor mounts and both worked again.

 

now get this when i went to drive it today i looked down and the speedo wasnt working and the tac was working but if i shut the truck off and start it 2 times and then drive it my speedo started to work again so my question is, is my cluster going bad or is there a sencer going bad or a bad ground somewhere thanks