Got a ECU error, 0903 EVAP Canister vent control valve.
Anyone know any details?

 

this might help

http://forums.maxima.org/showthread....hreadid=127018

 

There is an EVAP canister that collects moisture from your tank. It allows this moisture to pull out by venting the tank to atmosphere. Under throttle, you don't want this, you want your tank to pressurize. What the vent control valve does, is to sense the increase in manifold pressure and send a signal to the vent control solenoid to close it's valving and seal the fuel system from atmosphere.

Try cleaning/lubricating it as spiff56747...if that doesn't work, then buy new parts.