What causes excessive EGR flow?
Another common cause of excessive EGR flow has to do with the gasket used to create an air-tight seal between the EGR valve and its mounting surface. A damaged EGR valve gasket potentially allows exhaust to leak into your engine, even when your EGR valve remains in a closed position.
What causes P0402?
Code P0402 is triggered when the EGR temperature sensor sees more of a temperature change than the EGR has commanded to open. This is usually caused by the EGR backpressure control valve getting a burnt diaphragm from the exhaust backpressure over time or from a partly blocked catalyst.
What do you need to know about EGR codes?
A basic explanation of the valve works would probably help with the understanding of the diagnosis and repair of EGR codes. Exhaust gas recirculation is necessary for emissions purposes. Unfortunately, when it malfunctions it can actually push emission levels off the chart.
When to worry about an EGR valve problem?
If the initial reading is in spec but you have a trouble code for this system then it is possible that the system is not flowing when expected (EGR valve, EGR tube, DPFE hoses or control side issue), is flowing when it shouldn’t be (EGR valve or control side issue) or you may have an intermittent concern, possibly even with the DPFE sensor.
How to reset exhaust gas recirculation ( EGR ) value with?
5)Using a soft bristled tooth brush, scrub the EGR Valve, spray further cleaner into valve if needed. Once all traces of carbon are removed, using a lint free cloth dry the EGR Valve. 6)Disconnect vacuum pump or OBDâ…ˇ diagnostic tools.
How does the Ford EGR valve system work?
For simplicity’s sake we’ll base our diagnosis on a typical Ford EGR system. Let’s get started! So what is an EGR system and how does it work? EGR stands for Exhaust Gas Recirculation, and as its name implies, this system allows exhaust gasses from your car to be re-circulated into the engine, helping to reduce emissions.