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problems I cannot solve - 2004 V70R

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Pre-heating O2 sensor fault. The car run well, although i noticed higher consumption. Two more codes came on fuel pressure sensor and engine speed sensor. I finally decided to replace them. After I did it the car does not run. It starts an is running very rich, clouds of smoke and does not idle for more than a few seconds. Scanner does not show any other codes.  If I disconnect MAF sensor the car idles much better. I check it with a scanner again. No DTC now. Previously randomly fuel pressure sensor (after I installed the new one. 

Update:  I installed a new engine speed sensor - still no change. Trying everything I just disconnected the hose from charcoal canisters to intake manifold. (A horizontal fitting on the right side of the intake manifold - facing the engine). Checked the suction with a finger and suddenly engine idle smoothed to the normal, the engine reacted to the gas pedal much better then before and engine stopped smoking. Somehow I achieved almost ideal air-fuel mixture. As soon as I reconnect MAF sensor engine stalls. I switched the MAF sensor with a borrowed one - but no change. Where is the buried gremlin?

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