Could someone tell me what sensor sends the information to the tachometer? My issue is when the engine gets to normal operating temperature the tach will drop to zero for a few seconds and the engine might hiccup, but then everything goes back to normal. Any ideas?

 

Cam sensor located behind the Injection pump. Sends engine RPM, and the position of the Cam/Crank shaft as well.

 

Awsome, thanks!

 

Would this also cause transmission to downshift? I would be going down the road and my RPM needle would hit zero and the truck would downshift.