SL engine codes

[typhoontaz]

Hello,
I hope you can help me. I own a 1997 SL 600 that has a Vortech V-2 Supercharger on it. There is no air pump on the car, as the supercharger sits in the pump's location. I recently got the following codes:

P0105 Manifold Absolute Pressure/Barometric Pressure Circuit Malfunction
P0150 O2 Sensor Circuit Malfunction (Bank 2 Sensor 1)
P0422 Main Catalyst Efficiency Below Threshold (Bank 1)
P0300 Random/Multiple Cylinder Misfire Detected
P0307 Cylinder 7 Misfire Detected
P0308 Cylinder 8 Misfire Detected
P0309 Cylinder 9 Misfire Detected
P0310 Cylinder 10 Misfire Detected
P0311 Cylinder 11 Misfire Detected
P0312 Cylinder 12 Misfire Detected

I seems to run ok but now has a rough idle and surges at idle, I presume from the misfire. It does not backfire though. Any help would be greatly appreciated. Is this an O2 Sensor and if so which one?
Thanks again for all your help,
Scott

[Kebowers]

looks like the manifold pressure sensor went south, leaned out the mixture-or fuel pressure dropped out.

[typhoontaz]

Can you tell me the location of the map sensor and what it looks like?

[typhoontaz]

I found the map sensor. There was a little amount of oil in the line. I cleaned it and the map sensor. Is there a way to test the sensor to see it it works?

[typhoontaz]

Mystery solved. Apparently when I took the car into the dealer for a smog tune, the mechanic had disconnected a vaccuum line that ran to the idle air control valve. What a freakin pain. You know you pay a lot of money to have the dealer smog your car and this is what I get. Thank god it is fixed. 600hp is a lot better without a vaccuum leak.