Truck tries to die and the speedometer is jumping around even when stopped.

[Razorbackfan]

2001 Ford Ranger XLT 3.0L . Recently when I have driven the truck I noticed that my speedometer is jumping up and down from anywhere around 5 to 35mph, just bouncing up and down (when driving and sitting still). Now yesterday when I stopped at a light, the truck was bouncing between 5 and 35 again and like a quick flash the truck tried to die on me and all the dash lights went black and just as quick I was driving on my way with the bouncing speedometer. Anyone have any ideas what in the heck could be causing these issues??

 

[SenorNoob]

Pretty sure your year had electronic speedometer. If so I'm gonna guess bad power to the cluster or ground.

 

[bills4065]

2001 Ford Ranger XLT 3.0L . Recently when I have driven the truck I noticed that my speedometer is jumping up and down from anywhere around 5 to 35mph, just bouncing up and down (when driving and sitting still). Now yesterday when I stopped at a light, the truck was bouncing between 5 and 35 again and like a quick flash the truck tried to die on me and all the dash lights went black and just as quick I was driving on my way with the bouncing speedometer. Anyone have any ideas what in the heck could be causing these issues??

Try disconnecting the electrical connector on the alternator and take the truck for a drive.If the problem goes away- you probably have one or more bad diodes in the alternator.

 

[bills4065]

Your crankshaft position sensor is a 2 wire vrs type sensor. If this is starting to fail- this can give you some of the symptoms you are experiencing.