de mattydr67 » Joi Ian 27, 2011 10:48 pm
P0400 - Exhaust Gas Recirculation Flow Malfunction
OBD-II Trouble Code Technical DescriptionExhaust Gas Recirculation Flow Malfunction
What does that mean?The exhaust gas recirculation (EGR) valve is vacuum controlled valve that regulates the amount of exhaust gases that re-enter the cylinders. The powertrain control module (PCM) determines how much based on engine load, temp, and other conditions. If the PCM detects that the amount of exhaust gases entering the cylinder were insufficient or non-existent, this code is set.
SymptomsNo symptoms will likely be noticed by the driver other than the MIL (malfunction indicator lamp). However, non visible symptoms will be increased combustion temperature and increased Nox emissions.
CausesA code P0400 may mean that one or more of the following has happened:
Plugged EGR passage which restricts the flow of exhaust gasses
Faulty EGR solenoid
Faulty EGR solenoid wiring/harness
Vacuum lines damaged/disconnected to the EGR valve solenoid or to the EGR valve
Faulty EGR valve
Possible SolutionsSince EGR valve designs are different, no one test will suffice:
Using a scan tool, operate the EGR valve with the engine running. If the engine stumbles, the problem was likely intermittent wiring problem or intermittent blockage problem
If engine doesn't stumble, operate the EGR valve manually, if possible. If engine doesn't stumble and die, the ports are likely plugged. Removal of valve and cleaning of all ports will be required
Checking of solenoid can only usually be done with a scan tool, because most solenoids operate with a duty cycle of voltage, rather than constant voltage
Check all vacuum lines, hoses, etc for any damage
Visually inspect the solenoid harness and the solenoid for damage
Replace EGR valve
P0403 - Exhaust Gas Recirculation Circuit Malfunction
OBD-II Trouble Code Technical DescriptionExhaust Gas Recirculation Circuit Malfunction
What does that mean?The Exhaust Gas Recirculation (EGR) system is controlled by a vacuum solenoid. The solenoid is supplied ignition voltage. The Powertrain Control Module (PCM) controls the vacuum solenoid by grounding the control circuit(ground) or driver. The primary function of the driver is to supply ground for the object that is being controlled. Each driver has a fault circuit that the PCM monitors. When the PCM turns a component on, the control circuit voltage is low, or close to zero. When the component is turned off, the voltage on the control circuit is high, or near battery voltage. The PCM watches for these conditions, and if it doesn\'t see the proper voltage at the proper time, this code is set.
Potential SymptomsUsually a fault in the control circuit, will leave no noticeable symptoms other than the Malfunction Indicator Lamp (MIL) illumination. However, if the EGR control solenoid is stuck open due to debris, etc. the code may be accompanied by misfire under acceleration, rough idle, or engine dying altogether.
CausesThe causes for a P0403 EGR code could be any of the following:
Bad EGR solenoid
Excessive resistance in control circuit (PCM controlled ground) due to an open, chafing or damage to the harness
Poor connection at the EGR solenoid harness (worn or loose pins)
Water intrusion at the EGR solenoid harness
Blockage in EGR control solenoid holding solenoid open or closed causing excessive resistance
Loss of supply voltage to EGR solenoid
Bad PCM
Dupa cum vezi erorile spun cu torul altceva.
Sa nu cumva sa fi confundat tu erorile daca ( cred eu ca ai avut erori de genul P0300 si P0303 care se refera la rateuri care intradevar pot fi cauzate si de bobina defecta ) ai verificat cu si problema ar fi bobina de pe cilindrul 4. Si incazul asta codul de eroare ar fi P0404 adica pe cilindrul 4 si P0400 rateuri aleeatorii pe toti cilindrii.
Mai pune odata testerul si vezi exact codurile.
Sa nu le incurci.
Bafta