HAVE A SENSOR WITH A BLU AND GREY WIRE NEED TA KNOW WHERE THIS SENSOR CONNECTS ITS ON A 2002 CAVALIER 2.4L AND ITS NEAR THE EGR VALVE HARNESS

egr IS DEAD FIX EGR VALVE FIRST.
EGR DEAD CAUSES PING, HEARD OR NOT IT IS THERE.

MOST CARS THIS OLD THE VALVE IS BAD, OR JAMMED
OR IS PACKED UP FULL IN CARBON OR WORSE THE WHOLE
EGR PATH IS CARBON BLOCKED.

KNOCK 2 SENSOR LOSE? OR WIRES TO IT WRECKED.

DTC P1406 Exhaust Gas Recirculation (EGR) Position Sensor Performance
Circuit Description
The PCM monitors the EGR valve pintle position input to ensure that the valve responds properly to commands from the PCM and to detect a fault if the pintle position sensor and control circuits are open or shorted. If the PCM detects a pintle position signal voltage outside the normal range of the pintle position sensor, or a signal voltage that is not within a tolerance considered acceptable for proper EGR system operation, the PCM will set DTC P1406.
PCM - powertrain control module ,engine computer .
Diagnostic Aids
Check for the following conditions:
• Excessive deposits on EGR valve pintle or seat. Check for deposits that may interfere with the EGR valve pintle extending completely or cause the pintle to stick.
• Poor connection or damaged harness. Inspect the wiring harness for damage. If the harness appears to be OK, observe the EGR actual position display on the scan tool while moving connectors and wiring harnesses related to the EGR valve. A change in the display will indicate the location of the fault.
Important: If the EGR valve shows signs of excessive heat, check the exhaust system for blockage (possibly a plugged catalytic converter) using the Restricted Exhaust System Check.
Reviewing the Fail Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.

EGR is the exhaust gas recirculating valve . It's part of the emission system designed to lower emission of nitrates of oxygen. The vehicles PCM is sensing a problem with the flow or lack of flow thru the EGR valve. The EGR system has several components including the egr valve, erg solenoid, possible EGR temperature sensor and/or a DPFE ( differential pressure feedback sensor) and vacuum hoses. They are located on or near the intake manifold and connects to the exhaust manifold system also.

Check vacuum lines near EGR valves.

Diagnostic Trouble Code (DTC) P1401 indicates that the EGRP SIG circuit input is greater than the self-test maximum.

Possible Causes:

-- Damaged EGR Position sensor/EGR valve assembly.
-- Open in EGR Position sensor harness circuit.
-- Short to EGR Position sensor harness circuit.
-- Damaged EGR Vacuum solenoid.
-- Damaged EGR Vacuum solenoid harness circuits.
-- Damaged EGR Vacuum solenoid-valve.
-- Damaged PCM.

Hope this helps, also keep in mind that your feedback is important and I`ll appreciate your time and consideration if you leave some testimonial comment about this answer.

Fig. 4: Exploded view of the EGR system and related components for the 4.0L engine (click over pic for zoom)

REMOVAL & INSTALLATION

PFE/DPFE Sensor
This component is found on all engines, and is also referred to as the backpressure transducer.

1. Disconnect the negative battery cable.
2. Detach and label the wiring harness connector from the PFE/DPFE sensor.
3. Disconnect all of the hoses from the sensor.
4. Remove the mounting nuts, then separate the sensor from the mounting bracket.
5. If necessary, remove the EVR solenoid and the PFE/DPFE mounting bracket from the upper intake manifold.

To install:

1. If removed, install the EVR solenoid and mounting bracket onto the upper intake manifold.
2. If applicable, install the EGR tube heat shield.
3. Position the PFE/DPFE sensor on the mounting bracket, then install and tighten the mounting nuts until snug.
4. Attach all necessary hoses and wiring to the sensor.
5. Connect the negative battery cable.

EGR Vacuum Regulator (EVR) Solenoid
The EVR solenoid is mounted either on the same bracket as the PFE/DPFE sensor, attached to the upper intake manifold, or near the EGR valve on its own bracket.

1. Disconnect the negative battery cable.
2. Label and detach the wiring harness connector from the EVR solenoid.
3. Detach the main emission vacuum control connector from the solenoid.
4. Remove the retaining nuts, then separate the solenoid from the mounting bracket.

To install:

1. Position the solenoid on its mounting bracket and install the retaining nuts.
2. Attach the main emission vacuum control connector and the wiring harness connector to the EVR solenoid.
3. Connect the negative battery cable.

EGR Valve
See Figures 6 and 7

1. Disconnect the negative battery cable.
2. If necessary, remove the air inlet tube from the throttle body and air cleaner housing.
3. Label and detach all vacuum hoses from the EGR valve.
4. Label and detach any electrical wiring harness connectors from the EGR valve.
5. Disconnect the EGR valve-to-exhaust manifold tube from the EGR valve.
6. Remove the EGR valve mounting fasteners, then separate the valve from the upper intake manifold.
7. Remove and discard the old EGR valve gasket, and clean the gasket mating surfaces on the valve and the intake manifold.
   

Fig. 6: Cutaway view of a base entry type EGR valve

Fig. 7: Cutaway view of a side entry type EGR valve

To install:

1. Install the EGR valve, along with a new gasket, on the upper intake manifold, then install and tighten the mounting bolts to 4-22 ft. lbs. (20-30 Nm) on 3.8L engines, or to 106-49 inch lbs. (1-18 Nm) on 5.0L engines.
2. Connect the EGR valve-to-exhaust manifold tube to the valve, then tighten the tube nut to 30 ft. lbs. (41 Nm).
3. Connect all wiring or hoses to the EGR valve.
4. Install the air inlet tube.
5. Connect the negative battery cable.

Hope this helps, good luck (remember to rate this comments).

P1401 DPFE (Differential Pressure Feedback EGR) circuit high input: This code is in reference to the actual EGR valve monitoring sensor(DPFE). The actual circuit is damaged, thus, producing false negatives.The silicone rubber vacuum lines going to the sensor could also be faulty, as well. I would suggest to inspect the vacuum hoses that run to and from the DPFE sensor. If the hoses are in good shape; Replace the sensor, itself.

You could also check the EGR valve for faults, as well. If you have access to a hand vacuum pump, you can check the EGR passage quite easily with this device. Once you have gathered your pump; Disconnect and plug the vacuum line going to the EGR valve. Connect the vacuum pump to the EGR valve. Start the car and let it idle. Now, apply a simulated vacuum effect with the hand pump to the EGR valve. Your engine should stumble or stall if the passage is open. If it doesn't, the passage is clogged or the diaphragm in the EGR valve is bad. If the passage is open, it's most likely the DPFE sensor.


P1311 Ionization Misfire Detection Module Communication Fault: This code is not a normal ford code. With that said; I would advise to inspect all wiring that is running to the coils on this engine. This code will usually point to a failed coil or coil wire connection. i would also have each coil on this engine tested for their operational value. Check the entire engine harness for pinching or any damage that my be present.

what are the codes that made him think these two parts need replacing. The egr could cause a rough idle or stall, But it would need to be stuck open a little which may not set an egr code.

The crank sensor wouldnt cause a rough idle but the car could stall at times intermittantly.

What are you exact symptoms

These are different engines. You are about to open a big can of worms ,
I have not done this swap my self so if the engines do not look identical (ie DOHC MPFI)on the valve cover and air snorkle, I would look elsewhere for a decent 2002 model car because the 02 is a 2 valve per cyl. car and the 03 is a 4 valve per cyl. car and I can mostly guarantee the ECU wiring harness for them are different. not to mention there are different EGR locations on this 2,2.
This is a 'throw away" engine meaning it's not worth rebuilding.been there, got the t-shirt.

egr valve is usually located near the throttle body (the thing the accellerator cables go to) and it goes from the exhaust pipe to the throttle body, so anyhting from the upper intake manifold that connects to the exxhaust. It is about the side of a (or a bit smaller than) a snapple Iced tea jar/bottle.