1997-2001 Toyota Camry P0401 Diagnosis

One of the more common codes that I typically see on a 1997-2001 Toyota 2.2L 4-cylinder Camry is a P0401. It is a code that indicates that there is a problem with the EGR System, not necessarily a problem the EGR valve itself. I hear stories of people pulling getting this code and replacing the EGR Valve without doing any testing because they don't know what to test. They spend needless money and still haven't fixed the problem.

There are three parts that will generally make this code appear on your car. Yes the EGR Valve is one of them, but you also have the EGR VSV, and the EGR Modulator. The first parts of inspection will be to check the function of the EGR Valve by pulling a vacuum on it with a vacuum pump. You can get a vacuum pump at and auto parts store for around $20 and even rent one at some stores.