while sitting at an idle, my tach will slightly bounce. myabe 1/4". THe engine rpm does not change. is this a sign of my ckp sensor going out?

 

They all do it. Mine's done it since day one. Been fine for 50K miles and 2 years. Don't worry about it.

 

The tachometer, like everything else is controlled by the computer.
It's not an "actual" measure of really anything.

Same with the speedometer, oil pressure, engine temp, etc.

Perfectly within normal parameters.


phox

 

I thought I had a bad sensor. After reading this I am sure its normal.

 

Mine does the same thing. Like Big Blue and Phox said, it is normal with these trucks.

 

Mine did that since day one. However, at about 100,000 miles the CKP sensor went bad. After it was replaced, the tach does not bounce anymore. Unless you're throwing CKP codes, I wuoldn't worry about it.