Just an FYI for do-it-yourselfer's
 

To all,
This is just an FYI for anyone who may be doing the wrenching yourslf at home. I was getting a few codes on my Audi A6 2.7T Quattro... P1423 , P1411 , and P0748 with LIMP mode. The first two were giving me codes about air flow too low in banks 1 and 2 - secondary air flow system. The last code was a solenoid in the transmission - electrical throwing a LIMP mode when trying to start the vehicle.

I checked all my vacuum lines with no leaks. I checked my vacuum solenoid and fuses, which were fine. I finally decided to spray carb cleaner into both EGR valves and black carbon oozed out. I believe the EGR's were sticking and caused the codes in the secondary air flow system not allowing vacuum.

As for the transmission electrical code....I simply replaced my battery. The other battery was getting really bad and somewhere in THIS forum, someone sugested that eventhough there may be enough volts to start the car, there may not be enough amps to run electrical components such as solenoids....well they were right....no more LIMP mode or DTC's and engine lights.

Also replaced my driver side control arm myself with no problems other than getting the old one out...needed to buy a tie rod seperator...worked like a charm. Also had to lower sub frame down a little to get long bolt out of control arm.