change the egr valve
The generic OBDII descriptions are EGR Flow insufficient and EGR Flow Excessive.
egr passage way in engine plugged with carbon. will off of engine, make sure egr is ok.
The code depends on the manufacturer. Get it to autozone and have it tested, they will give you a printout of the most probable causes. What kind of car and engine is it? For a ford, p0401 insufficient flow within the egr system. it is most likely then a dpfe sensor or a clogged passage in the egr system. cheap fix.
p0401 is related to EGR valve flow. Possible bad EGR, check passageway under EGR to see if its plugged See also for the DPFE before changing the EGR Valve.
Carbon build up inside the EGR valve can cause a no flow code. The valve is located Ênear the center of the rear of the engine. It is held on by 2 bolts and a metal line.
It depends on what engine you have but the 02 is in the exhaust pipe or exhaust manifold and the EGR is a round disc shaped thing on the rear of the engine.
Start by replacing the DPFE sensor. Autozone about $35.00.newtest3
i need your help to fix this please i try everthing
the egr flow sensor is internal to the egr valve very common problem egr valve needs to be replaced
EGR { Exhaust Gas Recirculation} Flow Malfunction Early Exhaust Gas Recirculation (EGR) systems components include and EGR Valve, and Engine Control Μodule (ECΜ) Controlled Vacuum Switch Valve or EGR Solenoid and an EGR Vacuum Μodulator. Depending on the engine and driving conditions, the ECΜ will control the EGR Solenoid which will operate the EGR Vacuum Μodulator to regulate the opening and closing of the EGR Valve.
You buy a new egr valve for about $300.00 or take the old one apart and clean it. It fixed my 1990 3800 lesabre.