I have a 91 e350 4.9l ,c6 auto, have koer codes. first code is 311 second code is 332. sometimes when van is started it idles rough and runs rich, when is does this my scan tool will not connect to the computer then when engine seems to reach operating temp it idles up fast then comes back down and runs excellent like the computer has reset or something then my scan tool will connect to the pcm. also noticed when it goes crazy the fuel pump runs constantly when the key is in the on position normally it will run for a few seconds then shut off. i can tell it is going to start going crazy when the fuel pump does not shut off before i start the van. I have just replaced the fuel pump in tank and on the rail, fuel filter,fuel pressure regulator, tps sensor, idle air control valve, fuel pump and eec relay, ignition module and new o2 sensor and also a new negative battery cable because the old one was corroded and not grounded correctly. the van will sometimes go for days and has gone up to two weeks without going crazy. the parts that i have changed have solved codes 173 213 and code 411 that i had before. any help will be greatly appreciated i am about to go insane!!!!!!!!!!!!!!

 

You have the right person to help with the trip.
What might help would be to first swap the fuel pump and eec relays.
They should be both the same.
If that doesn't help, then you might remove the fuel pump relay and see if the fuel pump stops running with the key on and engine not started.
If the pump stops then, something is completing the ground to the relay instead of the computer. That should be the blue/org wire. Before I give your trip a rocket boost , how about you let us know what you find so far ?

I have some reservations regarding your scan tool and the codes it's giving you.

 

started checking for possible pcm ground problem. unbolted harness from pcm the ground pin looked like it got hot and melted the solder, any way when i unbolted the harness it pulled out of the pcm possibly from the bad ground cable on the battery. So far the van is running great. still have my koer codes 311 and 332 which i didnt expect to go away also have 332 in memory codes.the only thing i havent changed is the egr valve and i havent checked the egr ports for blockage. i have double checked all vacuum lines and hoses , new egr position sensor, new vacuum regulator,new fuel pressure regulator,throttle position sensor,map sensor,fuel pump,fuel pump relay,eec relay,O2 sensor, and tfi module. some of these parts are just for peace of mind had original fuel pump and tfi module. Also with this reman pcm the abs light is on in the dash. Smog pump seems to work fine i can feel it sucking air anyway

 

also the scanner i am using is an actron cp9190

 

The 311 code is related to the thermactor (smog) air system inoperative.
The 332 code is telling you the EGR valve movement has not been detected.
Could be EGR valve, position sensor, vacuum control. If you replaced the EGR position sensor , just disconnect the neg batt cable and codes will go away unless defect is still there.

 

First thing to check is the vacuum lines all over this thing: they have a really bad tendecy to crack and leak, and one broken line will cause both these codes.
One other thing to mention: if the 173 comes back, this means the O2 is stuck rich; check the fuel pressure. The press. reg. likes to stick (sometimes intermittanly) which will cause this.