crankcase vapors

[Jeanda]

motor- 3.4L/L32
symptom- poor idle/lopy idle @ start-up(then idles fine after warmed-up)
MAP sensor- reads above 2.50 volts @ idle(indicating vacuum @ idle is too low/should read below 2.0 volts)
possible cause- excessive crankcase vapor build-up
possible cause- faulty evap canister purge control silenoid valve(located in engine bay)
possible cause- faulty MAP sensor
possible cause- faulty PCV valve
possible cause- faulty evap canister valves(located in the drivers side rear wheel well)

...any other possible causes that I might have missed??

[94fbody]

Hi. I'd blame that F&*%ing EGR Valve system first-off, I know it gives me enough problems. Take it from me, I have a new EVAP canister, new MAP sensor, new PCV valve, BTW The Purge control solenoid and EGR valve are the same, just the names can be interchanged. My EGR valve continues to malfunction, robbing me of power and gas mileage, for some reason around the seat of my EGR valve, there appears to be oil/accumulated unburnt fuel/something like that gathering at the base and maybe I just simply have a manifold leak that is clogging the EGR system, who knows. I can tell you that my car, once warm will do fine but on start-up, your problems mimic mine. Oh, and why is it that '94 seems to be THE year for green 3.4L Camaro's Firebirds? Seems to be more of those than anything else for some weird reason, the 3.4's are everywhere!!

[pontiac nino]

Clean the EGR and piping, the throttle body, clean the crankcase ventilation system using pipe cleaners, replace the pcv valve (it's cheap)and see if that improves anything.