3.8l. scan code says that it has either a bad cam sensor or bad crankshaft sensor it runs but stalls out from time to time and at RPMs occasionally may stall

Crank and cam has the same power and ground wires tied together. The signal return are separate wires to the PCM. Guessing, I would say you have a bad/ broken wire at the crank sensor. The wires tend to break at the plugs. When you loose the cam sensor, the PCM goes into default mode. It will still fire the injectors. You just have lower gas mileage. When the crank sensor dies or can't be read. The engine will not start. No fire to the coil/s or plugs.

make, model, year? backfires are spontaneous burning (exploding) of unburnt fuel outside of the combustion chamber. suspect bad spark plug/s, ignition coils, ignition timing, computer, leaking fuel injector, etc. scan for trouble codes, then post back. because the problem is intermittent, problem manifests only when hot (engine at operating temperature) do tests for both cold & hot conditions. test resistances (ohm) of suspected sensors: cam & crankshaft position sensors, ignition coils (if possible),(search the web for the recommended procedures). also test voltages at the computer (search the web for the pin outs of the computer of your car). also check associated relays (like for the fuel pump, etc.) a bad relay may have its coil open when heated, then becomes good again when cold. i suspect the car may have a good fuel delivery but the sparks are not coming in on demand, thus backfiring.

code p0017 refers to crank/ cam oosition sensor bank 1 sensor B -correlation ===causes --wiring--CKP sensor--CMP sensor--mechanical fault.
It also refers to control modules, cooling fan--no signal===causes -- wiring--ECM.
If it has a timing chain then the the advice that it will not be the chain is good. So I suggest checking out the cam/ crank sensors and wiring

DTC P0016 - Crankshaft Position - Camshaft Position Correlation (Bank 1 Sensor A)
The crankshaft position sensor (CKP) and Camshaft position sensor (CMP) work in harmony to control the spark/fuel delivery and timing. They both consist of a reluctor, or tone, ring which passes over a magnetic sensor, which generates a voltage, indicating position.

The crankshaft sensor is part of the primary ignition system and functions as the "trigger". It detects the position of the crankshaft relays that information on to the PCM or the ignition module (depending on the vehicle) to control spark timing. The Camshaft position sensor detects the position of the camshafts and relays the information to the PCM. The PCM uses the CMP signal to identify the beginning of the injector sequence. What ties these two shafts and their sensors together is the timing belt or chain. The cam and crank should be precisely timed together. If the PCM detects that the Crank and Cam signals are out of time by a specific number of degrees, this P0016 code will set.

Symptoms of a P0016 will or may include:
Malfunction Indicator Lamp (MIL) illumination
The engine may run but with reduced performance
The engine may crank but not start
The engine may exhibit a rattle near the harmonic balancer indicating the tone ring is damaged
The engine may start and run, but poorly

Causes may include:
Timing chain stretched, or timing belt skipped a tooth due to wear
Misalignment of timing belt/chain
Tone ring on crankshaft slipped/broken
Tone ring on camshaft slipped/broken
Bad crank sensor
Bad cam sensor
Damaged wiring to crank/cam sensor
Timing belt/chain tensioner damaged

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It may be the crankshaft possitioning sensor. Hope this helps

bad crankshaft sensor or camshaft sensor
open and close the key 3 times and write down the codes tha come up on the cluster

Check the crankshaft sensor, that may be your problem, if you would list the code you got i could help some more, just because you got a cam code doesnt mean the cam sensor is bad, check the wiring also from the sensor.

Bad Idle, stalling, and engine in worst case will not start. The ECM take readings from the crankshaft and camshaft sensor to determine the engine's ignition timing and fuel injector timing.
A total sensor failure will cause the engine not to restart if there is no output reading form the sensor to the ECM. If there is an Auto Zone in your area, they can scan your car to address the issue if your crank/cam shaft sensor has gone bad and will need to be replaced.
Thank you for using fixya and Auto Zone scan free of charge and has the step by step instructions to get the job done.

if crank or cam sensor fails then it will cause hard time starting, shut off while driving, here are the fault codes--po340 is camshaft sensor. have car scanned at any auto parts place they will scan it for free. these two things will cause a problem code.

a bad crank sensor, or cam sensor will cause this--no start, hard time starting, shut off while driving. these will set a fault code. have engine scanned. auto zone will do this for free. p0340 is a bad cam sensor,