I drove my dodge Durango to day and when I got home I turn it off got out ,got back in to crank it up and it just kept turning over it never did cauth why

It wouldn't stop the engine from turning over while trying to start. But it can make engine not start or run poorly

Cam Sensor Failure Causing no Start or Stalling : Dodge ...

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Dodge Durango Cam Sensor Failure Causing no Start or Stalling. ... On the 4.7L V8engine, the Camshaft position sensor failure can cause the engine to crank but not start or it can ... On the 5.9L V8 engine, rerouting the ignition coil wire and spark plug wires can help solv. ... 1999 Dodge Durango ... Drove good till put gas.

Check the EGR valve... you really need to get a fault code reader of that thing so we can assist you better.

What's missing ? Fuel , spark . What condition is the battery in ? Fully charged 12.6 volts . When you turn the key to start does the starter spin the engine ? A crank no start or nothing happens when you turn the key to start . Videos on youtube ! Crank no start or no crank no start .

I would start by checking the basics which are checking for spark and fuel. If you have a gauge, check to see if you have fuel pressure when the key is turned on. If you have fuel pressure, check for spark. Chrysler products are known for the crank shaft sensor to go bad and cause a no start. Also, if driving for a certain period with the pedal depressed at the same speed, the throttle position sensor will stay at that position if stuck and will cause either and driveability problem or stalling. You may wanna look into replacing or at least checking that. Good luck.

You Might have a bad fuel pump.

Check the fuel pump relay, it should be in the underhood fuse box, and could cause the problem your describing. Buy one at the parts store ( quite inexpensive) and try replacing it before going to the pump itself.

I put in a new crank positioning sensor and it fixed my problem. 42.00 dollars from NAPA. took about 2 hours to change it.

I am guessing here but I would check the installation of your new cylinder and the fusebox. It sounds like the key is turning to the running/accessory position but not switching all of the accesories on. The tumbler can get loose inside the steering column and not engage the start switch.
Background... I had the same problem with 1st generation Dakota. The old key tumbler had to be turned much further than normal to engage the ignition. I paid "5 star" Dodge service to replace the unit and now it works as long as you turn the key back to "running" position after it starts. After the Dodge dealer told me that my truck was too old for them to be familiar they offered to dig around for MORE MONEY. Your problem reminds me that they said something inside the column wears out and they may not be able to fix. I was not impressed, but it reminds me to ask a mechanic if he intends to finish the job for which I am paying him. Mechanics aren't happy about this but it saves me money.

CHECK BATTERY, MAY BE GOOD TO TURN OVER BUT NOT ENOUGH VOLTAGE TO FIRE FUEL INJECTION SYSTEM. ALSO COULD BE A FUEL PUMP OR CRANK/CAM SENSORS..GOOD LUCK