Why did it fail the smog test?

https://www.google.com/search?q=2001+dodge+dakota+evap+system+diagram&rlz=1C1JZAP_enUS713US713&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwj9ot3N3oHVAhUJJiYKHbXHA-IQsAQIUQ&biw=1845&bih=990#imgrc=ZhkDDWeWf0B8wM:

Your mechanic will know. Eva= evap system, usually a vacuum leak somewhere. Vacuum leaks will also affect idle.

Trouble Code: P0134

HO2S-11 (Bank 1 Sensor 1) No Activity Detected

Trouble Code Conditions: Engine started, engine running in closed loop at a speed over 3 mph for more than 2 minutes, and the PCM detected the HO2S signal stroke rationality was more than the threshold value (0.250 volt) during the Heated Oxygen Sensor Monitor test.

Possible Causes:


HO2S signal circuit is open or shorted to ground.HO2S has deteriorated, is contaminated or has failed.PCM has failed.YOUR HO2S SENSOR IS BAD,IT COST 80.00,USE EXACT FIT PART.EASY TO REMOVE,DISCONNECT ELECTRICAL CONNECTOR,GET WRENCH AND REMOVE.5 MINUTES TO DO.Trouble Code: P0336

Crankshaft Position Sensor Performance

Trouble Code Conditions: Engine running and the PCM detected the number of CKP sensor signals counted (between the reference mark gap). did not equal the Actual number of available teeth (i.e., the CKP signals. were out or the normal window" of operation with the CMP sensor. signals okay).

Possible Causes:


CKP sensor signal circuit connections loose (intermittent fault).CKP sensor wiring harness has a connection fault (intermittent).CKP to Target Wheel "air gap" is incorrect.CKP sensor is damaged or has failed.Must remove to see.Trouble Code: P0440

EVAP System Malfunction

Trouble Code Conditions: Engine started, ECT sensor signal less than158?F at startup, IAT sensor signal more than 9.5?F, system voltage over 10.0 volts engine runtime 15-20 minutes at cruise speed, then returned to idle speed, VSS indicating 0 mph, load value 2.2 ms, canister load factor less than 4.0, fuel tank pressure less than 0.5" Hg, then after the Idle Control system and Fuel Trim had stabilized, the PCM detected a fuel vapor leak (as small as 0.040") in the EVAP system during the EVAP Leak Test.

Possible Causes:


Fuel filler cap damaged, cross-threaded or loosely installed.Small hoses or cuts present in the EVAP vapor hoses/lines.EVAP purge valve is damaged or has failed.Here you are the symptons.

This is the generic definition for the code.
Your year and model may be different. Possible causes include a faulty purge control valve or the circuit back to the computer.

P0443 Description The Evaporative Emission System (EVAP) canister purge volume control solenoid valve uses a ON/OFF duty to control the flow rate of fuel vapor from the EVAP canister. The EVAP canister purge volume control solenoid valve is moved by ON/OFF pulses from the Engine Control Module (ECM). The longer the ON pulse, the greater the amount of fuel vapor that will flow through the valve.
Read more: http://engine-codes.com/p0443.html#ixzz27RdAClP2

OBD II Code P0442

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Evaporative System Malfunction, Small Leak Our emissions expert has put together the following information about the P0442 fault code. We have also included diagnostic procedures you can take to your repair shop if the mechanic is having difficulty analyzing the code.
Related Information Check Engine Light
Emission Gas Definitions

OBD II Fault Code

• OBD II P0442

Fault Code Definition

• Evaporative System Malfunction, Small Leak

Symptoms

• Check Engine Light will illuminate
  
• In most cases, there are no adverse conditions noticed by the driver
  
• In some cases, there may be a noticeable fuel odor caused by the release of fuel vapors

Common Problems That Trigger the P0442 Code

• Defective or damaged fuel cap
• Distorted or damaged Fuel Tank Filler Neck
• Small tear or puncture in the Evaporative system hose(s) and/or Carbon Canister
• Defective Fuel Tank Sending Unit gasket or seal
• Small split in a seam of the Carbon Canister
• Defective Evaporative Vent Valve and/or Evaporative Purge Valve
• Defective or damaged Fuel Tank
• Defective Fuel Tank Pressure Sensor
• Defective Leak Detection Pump
• Slightly loose and/or worn clamps or hardened O-rings anywhere in the EVAP system

Common Misdiagnoses

• Fuel cap
• Evaporative Purge Valve
• Evaporative Vent Valve

Basics
The evaporative control (EVAP) system captures any raw fuel evaporating from the fuel storage system (e.g. the fuel tank, filler neck, and fuel cap). Under precise operating conditions-dictated by engine temperature, speed, and load-the EVAP system stores and purges these captured fuel vapors back into the combustion process.
Want to Learn More?
The EVAP system is designed not only to capture, store, and purge any raw fuel vapors that leak from areas in the Fuel Storage system, but also to run a series of self-tests that confirm or deny the operational and vapor holding ability of the system. This is an important task because at least 20 percent of vehicle-produced air pollution originates from malfunctioning Vehicle Fuel Storage systems.
There are many ways to "leak test" the EVAP system, but most perform the leak test when the vehicle is sitting (like over night) or during the initial start-up after the vehicle has been sitting over night. The EVAP system's operational performance is also tracked by the Power Train Computer by reading the change in the oxygen sensor voltages and short term fuel trim whenever the stored vapors are released or "purged" back into the combustion process. These values should indicate that fuel is being added to the system and that the overall mixture is getting richer. The purging process occurs when the vehicle is under acceleration, which is when most vehicles require additional fuel.

P0442 Diagnostic Theory for Shops and Technicians
The P0442 code indicates that there is a small leak in the EVAP system, but this is somewhat misleading. What the code really indicates is that the EVAP system will not hold a specified level of vacuum for a specified amount of time when it performs its leak test.
Here is how the evaporative leak test is performed by the Power Train Computer:

1. When the leak test is performed, the vehicle must have been sitting for at least four to eight hours so that the engine temperature and outside air temperature are identical. There must also be between 15 and 85 percent fuel in the tank-this is to provide a baseline for the test since gasoline and diesel are volatile fluids that expand and vaporize easily with warm temperatures.
2. When the leak test initiates, the Vapor Canister Vent Valve is closed to prevent any fresh air from entering the EVAP system. The Purge Valve is also sealed off.
3. The Leak Detection Pump operates to build a vacuum in the entire Evaporative System (see the Leak Detection Pump information below). After a specified time interval-usually about ten seconds-the Purge Valve is shut off and the vacuum level in the system is measured by the Fuel Tank Pressure Sensor.
4. Finally, a countdown initiates, which measures the rate at which the vacuum decays in the system. If the vacuum decays faster than the specified rate on two successive tests, then the Power Train Computer will fail the EVAP system and trigger the P0442 code. Most modern EVAP systems will fail the leak test with a pin-sized hole anywhere in the EVAP system, which amounts to 0.020 of an inch or a ½ millimeter.

Did they explain the fuel evap test to you and what may have caused you to fail? Most smog tests that I've dealt with only test your gas cap and don't actually test your evap system itself. Gas cap is part of your evap system so when the cap fails, you automatically fail your evap system test even though they don't actually test it.

I recommend replacing your gas cap and giving it another shot as the cap will cost $10 to $20...

EVAP is evaporative emissions which include the raw fuel vapors from the tank. They are known as hydrocarbons. The evap system contains these vapors and disposes of them through the burning process in the engine. You have valves and solenoids controlled by the computer to purge them from the system. Some of the parts that may cause this test to fail are the vapor lines to and from the tank, the fuel cap (loose or leaking), the carbon canister, and the purge valve or solenoid. It is a somewhat difficult system to test because it is under very low pressure. With all the components in the system, it is hard to say which is at fault. There is a pressure tester provided by Rotunda (Ford service tool) that is made to diagnose this particular problem. You local dealer should have one. About all you can do yourself is visually check the lines and the fuel cap for obvious problems. The MIL light may be on for this reason also. I hope this helps.

replace the pvc valve and have the egr valve replace.make sure the vacuum hoses connect to egr valve and pvc replace.change air filter.all those things will cause high emission if not working properly.cause you to fail smog test.

P1747 * EPC, wiring, PCM EPC solenoid circuit failure, shorted circuit or output driver Voltage through EPC solenoid is checked. An error will be noted if tolerance is exceeded. Short circuit causes minimum EPC pressure (minimum capacity) and limits engine torque (alternate firm). Go To Pinpoint Test
The EPC solenoid is shorted or the electrical circuit (wiring) or the transistor (driver) inside the computer is fried. do you know how to test a computer controlled circuit ?
How to test computer transistor driver without scan tool

Do you know how to find the circuit in question ?

And you are correct about these two codes as being not related . Do you know what evaporative emission system is ?


Wells EVAP Training with Sgt Tech P0440 P0441 P0442 etc

The Evaporative Emission Control System (EVAP) is used to prevent gasoline vapors from escaping into the atmosphere from the fuel tank and fuel system. The EVAP system usually requires no maintenance, but faults can turn on the Check Engine light and prevent a vehicle from passing an OBD II plug-in emissions test.
EVAP Evaporative Emission Control System - AA1Car.com
http://www.bbbind.com/free_tsb.html you can find free wiring diagrams here . Do you know how to use a wiring diagram ?

P1451 - EVAP Control System Canister Vent Solenoid Circuit Malfunction Monitors the canister vent (CV) solenoid circuit for an electrical failure. The test fails when the signal moves outside the minimum or maximum allowable calibrated parameters for a specified canister vent duty cycle by PCM command.

• VPWR circuit open
• CV solenoid circuit shorted to PWR GND or CHASSIS GND
• Damaged CV solenoid
• CV solenoid circuit open
• CV solenoid circuit shorted to VPWR
• Damaged PCM

To verify normal function, monitor the EVAP canister vent solenoid signal PID EVAPCV and the signal voltage (PCM control side). With the valve open, EVAPCV will indicate 0% duty cycle and the voltage approximately equal to battery voltage. When the valve is commanded fully closed, EVAPCV will indicate 100% duty cycle and a voltage drop of 4 volts minimum is normal. Output test mode may be used to switch output ON/OFF to verify function. This is another electrical circuit problem .
Do you know how to use a DVOM - digital volt ohm meter ?
Do you know that P1747 (electronic press control solenoid short circuit) Is a transmission problem . This solenoid controls the fluid pressure .

CHECK AND CLEAN I.A.C SENSIOR