check engine codes 300 404 for a 2003 Chevrolet Impala with 80k miles. Spark plugs have been replaced. Car has a bad EBCN on it.
Circuit Description The exhaust gas recirculation (EGR) valve position sensor is monitored by the powertrain control module (PCM). The 5-volt reference circuit, low reference circuit and the EGR valve position signal circuit are used by the PCM to determine the EGR valve position. The PCM compares the EGR Position Sensor parameter with the desired EGR Position parameter when the valve is commanded open or closed. If the PCM detects a calibrated difference between the EGR Position Sensor parameter and desired EGR Position parameter for a calibrated amount of time, when the EGR valve is commanded open, DTC P0404 sets.Conditions for Running the DTC
Conditions for Setting the DTC
Action Taken When the DTC Sets
Conditions for Clearing the MIL/DTC
ASE MASTER TECH L1 ADVANCED DIAG, 18 YEARS EXP, 6 YEARS GM TECH, 12 YEARS ALL MAKES ALL MODELS
SYSTEM DESCRIPTION The powertrain control module (PCM) uses information from the ignition control (IC) module and the camshaft position (CMP) sensor in order to determine when an engine misfire is occurring. By monitoring variations in the crankshaft rotation speed for each cylinder, the PCM is able to detect individual misfire events. A misfire rate that is high enough can cause the 3-way catalytic converter (TWC) to overheat under certain driving conditions. The malfunction indicator lamp (MIL) will flash ON and OFF when the conditions for TWC overheating are present. If the PCM detects a misfire rate sufficient to cause emission levels to exceed mandated standards, DTC P0300 will set.CONDITIONS FOR RUNNING THE DTC
CONDITIONS FOR SETTING THE DTC The PCM is detecting a crankshaft rotation speed variation indicating a misfire sufficient to cause emission levels to exceed mandated standards.ACTION TAKEN WHEN THE DTC SETS
CONDITIONS FOR CLEARING THE MIL/DTC
Car is not with me Son has it in Akron Ohio. Should I have the EGR replaced first? He is not from the area and is new in town. I am in Dallas Texas. Since this car has a bad EBCM that is waiting to be replaced would that cause the PCM to act up?
yes, replace egr, this would be the most likley cause, if no diag is possible, and no the ebcm would not cause these codes. and if the egr is bad it can cause missfires as well.