Nissan Repair: 2001 Altima Idles rough, altima gxe, cylinder misfire

Question
My 2001 Altima GXE idles very rough when I come to a stop.  I've replaced the plugs, distributor cap and rotor button. I took it to a mechanic to pull the error code because the check engine light was on, however I suspect they were using an older scanner because the error they got was "random/multiple misfire".  It is still idling rough and the check engine light is back on.  I suspect it could be either an 02 sensor or IAC, but I wanted to check for some expert advice before I get in to deep.
Any help is GREATLY apprecatied.
Thanks!


Answer
Clay,

I would bet the distributor was defective since you have the code for multiple cylinder misfire.  I have seen where plugged injectors have caused the problem or a fuel pump that was not dumping fuel at idle.  Remember that there is a pressure regulator that has to bleed off fuel pressure.  And the cheap Nissan design does not cycle fuel to and from the engine like the older ones.  The fuel pump is in the tank and the regulator and fuel filter are all in there with it.  So, when it clogs the pressure spikes at idle and the engine sputters.