baskervi1

We've had this Suburban for about 2.5 years. A week or so after we purchased it, the check engine light came on with a P0446 error code (EVAP purge/vent solenoid circuit condition). At the time, I tried a few things, but if it ever did go out, the error code eventually came back, but I wasn't too worried about that.

A few months ago, we had a light come on the dash about a 4WD problem, so we had this diagnosed by a local auto parts company. At the time, I'm pretty certain they said I needed a 4WD solenoid, but after returning home and doing a little research, I decided he meant an actuator on the transfer case. I don't recall the error code for this.

I finally decided to replace it today because we had a tough time getting the Suburban out of 4L into 2H, but after taking the truck in to get the error codes and parts, a slew of error codes were displayed:
P0446 - EVAP purge/vent solenoid circuit condition
P0116 - Engine coolant temp circuit
U1073 - Lost communications with body multiple control system
C0300 - Rear propshaft signal circuit malfunction
C0321 - Transfer case lock circuit malfunction
C0374 - General system malfunction
C0550 - ECU malfunction
B2725 - mode switch circuit malfunction
U1301 - Class 2 data link high

I've found possible solutions to all of these, but I find it odd that so many things went out all at once in a fairly short amount of time. I'd like to think there is a root cause that will fix a number of these problems. Can any one give me his opinion? I'd greatly appreciate any help and guidance.