EGR valve and rough idle on 2000 Toyota Camry

I have been reading posts regarding EGR valves because my sons check engine light came on. Advance auto did a scan which showed code P 0401: Egr valve insufficient. Could the egr valve problem be related to a slightly rough idle that he has experienced

Asked by for the 2000 Toyota Camry
That is a possibility, and should be done. I believe you idle quality is related to a carboned & sludge up air induction system. Get a complete FUEL INJECTION SERVICE.
Vehicle Application: 1996 Toyota Camry DX 2.2L 1998 Toyota Celica GT 2.2L
1996 Toyota Camry LE 2.2L, Vin G, Eng Cfg L4, Eng Des 5SFE 1999 Toyota Camry 2.2L, Eng Cfg L4, Eng Des 5SFE
1997 Toyota Camry CE 2.2L, Vin G, Eng Cfg L4, Eng Des 5SFE 2000 Toyota Camry 2.2L, GAS, Eng Cfg L4, Eng Des 5SFE
1997 Toyota Camry CE 3.0L, Vin F, Eng Cfg V6, Eng Des 1MZFE 2001 Toyota Camry 2.2L, CNG, Eng Cfg L4, Eng Des 5SNFE
1997 Toyota Camry LE 2.2L, Vin G, Eng Cfg L4, Eng Des 5SFE 2001 Toyota Camry 2.2L, GAS, Eng Cfg L4, Eng Des 5SFE
1998 Toyota Camry 2.2L, Vin G, Eng Cfg L4, Eng Des 5SFE

Customer Concern: The check engine light is on with a trouble code P0401.
Tests/Procedures: 1. Verify that the vehicle will stall at idle when the Exhaust Gas Recirculation (EGR) valve is opened.

2. Monitor the vacuum signal to the EGR valve, while driving the vehicle, and it should be 3 to 7 inches. If the vacuum is low, verify that the ports are clean and the intake and EGR vacuum modulator operate correctly.

3. Next, verify that the EGR Vacuum Switching Valve (VSV) under the intake is not causing the low vacuum signal to the EGR valve. Also, verify that the EGR VSV is turning on and off by the Engine Control Module (ECM) when driving the vehicle and when the engine is cold. When everything checks OK, the EGR VSV is the common failure. It can test just fine and cause the code to set.

4. Check and clean the filter located in the intake manifold that supplies the vacuum signal to the Manifold Absolute Pressure (MAP) sensor.

5. Verify that the O2 sensor functions correctly and does not cause any type of surge when driving.
Potential Causes: ECM
EGR Vacuum Modulator
Exhaust Gas Recirculation (EGR) Vacuum Solenoid Valve (VSV)
Exhaust Gas Recirculation (EGR) Valve
MAP Sensor Vacuum Filter
Vacuum Supply

Tech Tips: The EGR VSV is located on the bottom of the intake manifold.
Diagnostic Codes: P0401
Thank you so very much! you tech are awesome!! My son has an appointment with Firestone Carcare on tuesday and he can take this response with him to suggest the service bullitin notice.
Just curious what did you do to fix the problem?
3 answers 4 comments
Yes, it is possible that it is related. Simply remove the EGR valve and clean it very good. The problem should go away.
I just had the EGR valve fixed. The rough idle was related and is now resolved.
I have a 1994 Toyota Camry 2.2 auto, When I start it up it Idles just fine but when It warms up I develop a rough idle/ idle hunting. I tried to use some carb cleaner to clean the EGR valve, It seemed to work for awhile. After a few minutes it would stumble again. Fuel filter, air filter pcv valve and plugs and wires have been replaced. HELP!!!