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AO Silver Member
Join Date: Nov 2007
Check your airflow at idle when EGR valve is closed (turn on the car and let it idle a few minutes, when EGR closes, check parameter "intake air quantity"), airflow should be ~480mg/inj when EGR is closed (you can check that EGR is closed if the parameter "EGR valve opening is 1%").
If you see lower airflow numbers than 450mg/inj, this could be either EGR valve issue, or clogged intake manifold.
You can try blanking off the EGR valve, and trying again with MAF sensor connected.
Does it smoke with the sensor plugged/unplugged?
If it smokes only when the sensor is unplugged, then there is a good chance the MAF sensor is OK, and it reports correct values. Then you need to check what is the cause for low airflow reading (maybe clogged intake, or even something like engine being slightly out of phase)...