I Want to fix my error codes on my car but dont no what they are the codes are P0402-- Exhaust gas recirculation Flow Excessive Detected P1131--Lack of H02S11 Switches Indicates Lean Please Help i already Replaced My EGR Vacuum Solenoid that fixed one code from before But i still got 2 left..

P0402 is an OBD-II generic code that the engine control module (ECM) has detected indicating the engine exhaust gas recirculation (EGR) valve is flowing too much recirculated exhaust gases when it is commanded to open the flow of gases into the intake manifold.

DTC P0402: Exhaust Gas Recirculation (EGR) Flow Excessive

The engine control module (ECM) tests the exhaust gas recirculation (EGR) flow when the EGR is in operation. EGR desired flow is compared to EGR actual flow. If EGR flow is higher than expected DTC P0402 will set.

Do you know what EGR is ?

www.yourmechanic.com/article/p0402-obd-ii-trouble-code-exhaust-gas-recirculation-flow-excessive-detected- Please go here for a detailed account of the cause. God-Bless!

code p0402 refers to exhaust gas recirculation (EGR) system--excessive flow detected===causes--hose blockage/leak--basic setting not carried ouit(if applicable) wiring--EGR valve--EGR solenoid ---ECM
replace the valve and solenoid.

This is not a cut and dry fault code. This means that more than one thing wrong can set the code in the computers memory. Here is the low down on the P0402 fault code. This is from the OBD2 fault code diagnostic book.

P0402 - Exhaust Gas Recirculation Flow Excessive Detected
Symptoms - Engine Light ON (or Service Engine Soon Warning Light)
- Possible engine hesitation
Possible causes - EGR solenoid valve harness is open or shorted
- EGR solenoid valve circuit poor electrical connection
- EGR volume control valve stuck closed
- Dead (Weak) battery
- Faulty EGR temperature sensor and circuit
- Faulty EGR Valve
- EGR passage clogged
- Exhaust gas leaks

CODE PO402 EXHAUST GAS RECIRCULATION SYSTEM EXCESSIVE FLOW DETECTED.POSSIBLE CAUSE EGR PIPE IS CLOGGED RESTRICTED.OR EGR SOLENOID VALVE CLOGGED OR FAILED.

P0402 OBD-II Trouble Code - Exhaust Gas Recirculation Flow (EGR) Excessive Detected

What does that mean?
EGR stands for Exhaust Gas Recirculation. It is part of the vehicle emmissions system, and is used to reduce combustion temperature and pressure to control Oxides of Nitrogen. There are generally three parts to the EGR system: the EGR valve, an actuator solenoid, and a differential pressure sensor (DPF). These things work together to deliver the correct amount of recirculation based on engine temperature, load, etc. The P0402 code means that OBD detected an excessive amount of EGR.

Symptoms
You may notice drivability problems such as the engine may surge off idle. There may also be other symptoms.

Causes
A code P0402 most likely means one or more of the following has happened:
* The DPFE (differential pressure) sensor is faulty and needs to be replaced
* There is a blockage in the EGR (most likely carbon buildup)
* The EGR valve is faulty
* The EGR valve may not be opening due to a lack of vaccuum

Possible Solutions
With a P0402, it is common for people to replace the EGR valve, only to have the problem return. The most likely solution is to replace the DPFE sensor.
* Check the voltage at the DPFE sensor both at idle and when the EGR is open
* Replace the DPFE sensor

Hope helps (remember rated and comment this).

Exhaust Gas
Recirculation Flow (EGR) Excessive Detected A code P0402 most likely means one or more of the following has happened:

• The DPFE (differential pressure ) sensor is faulty and needs to be replaced
• There is a blockage in the EGR (most likely carbon buildup)
• The EGR valve is faulty
• The EGR valve may not be opening due to a lack of vaccuum

this means exactly what it says, the emission control valve is faulty and needs replacing.
Basically the valve is in an open position when it should be shut or partially shut.
Replace the valve and this should cure both codes.

P0402 Exhaust Gas Recirculation Flow Excessive Detected
replace the EGR valve position sensor