'99 Camry I4. Pulled code P0401, P0446.

I have replace the EGR valve, EGR modulator, and EGR VSV with Toyota parts. Still get the code. When reving the engine while parked, the EGR Valve kicks in (vacuum applied) for a second and then releases (no vacuum). The VSV seems to be working, with the engine off (VSV solinoid not energized), air passes through the valve from the modulator to the EGR valve. With the ignition in standby, the VSV is energized and air does not pass.

I bypassed the VSV valve so the EGR valve gets vacuum all the time, still get P0401 (insufficient flow) code, which made no sense to me.

Can this code be caused by a bad sensor? The car runs fine but I have an emissions test due and don't know if it will pass.

Any ideas appreciated, I have read as much P0401 on camry's I could find, mostly the VSV but mine is new. Thanks.

Have you read the relevant post in the FAQ thread?

http://www.automotiveforums.com/vbulletin/showpost.php?p=3203705&postcount=21

Hey GIT did you fix the problem? did you replace the MAP sensor? my 99 just came up w/ the same codes ( p0401 and p0446 ), i ve replaced the EGR valve so far , but was curious what you did before i proceeded.
thanks in advance
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