Fluctuating Idle with P0401 and P0402 codes on 1999 Toyota Camry

I had 1999 Camry engine replaced recently. The idle needle pin fluctuate as the engine become hot. The codes are P0401 and P0402. I had it replaced EGR modulator, EGR valve and EGR solenoid. Did not fix. I clean throttle body with carbon cleaner and spray the hole to IAC inlet. Nothing changed. What could be the reason and the solution to it. In a youtube video bad DPFE sensor (EGR position sensor) causes P0401 to come up. However, someone in the forum says there is no EGR position sensor with this model. I need helps...

by in Indianapolis, IN on May 15, 2014
1 answer 1 comment
ANSWER by on May 16, 2014
fluctuating idle most likely cause is bad idle control valve as for the codes need test egr switching valve if is a 4 cylinder engine is located under intake manifold and check vacume diagram to ensure hoses connected correctly
COMMENT by on May 16, 2014
When I disconnect the hose that goes from modulator to EGR valve, the idle is normal. Could it still be the IAC problem?

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