I got a code P0016 Changed the crank & cam sensors. still have code and won't idle.

There could be many causes other than straight forward replacing the sensor.
P0016 Causes

• Frayed cam sensor wiring
• Frayed crank sensor wiring
• Faulty timing belt/chain
• Defective tone ring
• Faulty cam sensor
• Faulty crank sensor
• Faulty ECM

code p 0016 refers to crank shaft or cam shaft position sensor bank 1 sensor A----correlation===causes ---wiring---CKP sensor--- Cam sensor--- mechanical fault

P0016 fault is poor crank/cam correlation. In other words the signals the ECU is receiving from the crank and/or cam sensors isn't making any sense and this could be caused by bad cam timing, wiring, connectors or the ECU itself or by faulty sensors but as you have changed these, probably not.

You replaced the cam sensor or the cam phaser solenoid?

did you do a cam/crank relearn?

is it running rough at idle?

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

Check to see that the wiring going to the cam sensor is good. Have you pulled the codes? If not, you should get a code reader. If you pull a P0016 code, then it's mechanical failure. Your timing jumped.

P0016 Crankshaft Position - Camshaft Position Correlation
P0135 O2 Sensor Heater Circuit
P0138 O2 Sensor Circuit High Voltage
P0340 Camshaft Position Sensor "A" Circuit
P0344 Camshaft Position Sensor "A" Circuit Intermittent
P0508 Idle Air Control System Circuit Low
P0522 Engine Oil Pressure Sensor/Switch Low Voltage
_____________--
JMA TRS-5000 Cloning Machine

P0016 is for camshaft/crankshaft misalignment. You should check and verify that the timing chain is still intact and that the cam/crank timing is correct. If the engine is cranking really fast and does not sound like there is compression, it is probable that this chain/chains have jumped &/or broken.

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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P0016-CRANKSHAFT/CAMSHAFT TIMING MISALIGNMENT
Does the car run? If it doesnt run it may have slipped time.If it does run, use a scope if available and check for a weak or erratic signal from the cam and crank sensors. The cam sensors routinely go out on these cars but a bad crank sensor can cause the code also.

there you go the timing is off:

http://www.obd-codes.com/p0016

alignment for timing:

http://www.2carpros.com/diagrams/toyota/avalon/2003