1999 Toyota Camry Q&A

1999 Toyota Camry Question: Fluctuating Idle with P0401 and P0402 codes

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... -
Answer 1
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 1
When I disconnect the hose that goes from modulator to EGR valve, the idle is normal. Could it still be the IAC problem? -