i have a 2001 dodge ram 1500 5.9l auto 4x4, I haven't been driving it much this summer, a couple of weeks ago i went to start it and it started backfireing and when i put it in reverse it stalls, I put my code reader on it and it said camshaft positioning sensor, so i put a new one on and the same thing, it sounded like a timming issue so i checked the timming and it was good, put on new distributor cap and rotor button and plugs, still the same thing. Now this is where things get confusing it backfires and stalls in park and reverse only, put it in neutral or drive and it runs and drives fine, once it warms up it will run fine in park and reverse. so i changed the coolant temp. sensor and still the same thing. i noticed when it is cold it doesn't want to shift right and when it does it shifts hard. my speedomerer stoped working a year ago long before all of this, it has came up on the code reader speed sensor malfunction before this aswell, but now it is not giving any codes. can someone please help me,
Thanks.

 

Check this out, not that it's a solution -- https://dodgeforum.com/forum/2nd-gen...um-thread.html

Take out front O2 sensor from the bung. Zip tie it off but don't let it bang anything. See if anything changes.

Get a can of seafoam and follow directions to use it.

Did the code clear after CPS changed out?

Did you have battery negative disconnected both times sensors being tossed in there; CPS and Temp?