I have a 2000 dodge ram 2500 24 valve 4x4 when I am driving the tac will be at 2000 rpm and then go to 1000 rpm ,it jumps back and forth in over drive or out of o/d. I checked code and it was p1693 if you could help it would be great thx need to get home!! im new at this I hope I posted this in the right place

 

Welcome to the site, your problem is probably the CAM position sensor located behind the VP injector pump but can be changed without removing the VP, It's a fairly common problem. here is a link to a thread about the cam sensor replacement, 2001/02 only have a cam sensor no crank sensor.https://www.dieseltruckresource.com/...osition+sensor oops sorry I read 2002.

 

I will check it out thx a lot

 

Hook up a quality code reader and see what other code is in there besides the 1693 which is a companion code.

 

katoom is right on. get the other code from a scan tool instead of cycling the key 3 times. youll get whatever codes are on the other computer.

 

Crank sensor controls the tach. 01 it was eliminated