Check engine light and ESP light - several ODB II error codes - A4 1.8L 2003
 

I was driving and the ESP light came on. When I restarted the car the CEL was on. I had the codes read and reset. The lights came back on right away after restarting the car.
The codes were

P0445 Evaporative Emission Control System Purge Control Valve Circuit Shorted
P0037 HO2S Heater Control Circuit Low (Bank 1 Sensor 2)
P0418 Secondary Air Injection System Relay "A" Circuit Malfunction
P0414 Secondary Air Injection System Switching Valve A Circuit Shorted
P2401 Evaporative Emission System Leak Detection Pump Control Circuit Low
P0141 02 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2)
P0102 Mass or Volume Air Flow Circuit Low Input
P0031 HO2S Heater Control Circuit Low (Bank 1 Sensor 1)

I was wondering if a fuse might have blown or if i really need an o2 sensor replaced. I had both o2 sensors replaced 1.5 years ago!

I have the same problem, did you ever figure out what the issue was? I would really appreciate it.

O2 sensor Bank 1 Sensor 1 & 2:
P0031 http://engine-codes.com/p0031_volkswagen.html
P0037 http://engine-codes.com/p0037_audi.html
P0141 http://engine-codes.com/p0141_audi.html

EVAP System:
P0445 OBDII Code P0445 AUDI - EVAP System Purge Control Valve Circuit Shorted | Engine-Codes.com
P2401 OBDII Code P2401 - Evaporative Emission System Leak Detection Pump Control Circuit Low | Engine-Codes.com

MAF Sensor:
P0102 OBDII Code P0102 AUDI - Mass or Volume Air Flow Circuit Low Input | Engine-Codes.com

Air Injection System:
P0414 OBDII Code P0414 AUDI - Secondary Air Injection System Switching Valve 'A' Circuit Shorted | HelpForCars.net
P0418 OBDII Code P0418 - Secondary Air Injection System Relay 'A' Circuit Malfunction | Engine-Codes.com

The MAF and O2 Sensor codes can affect engine performance. The AIR and EVAP codes do not affect performance, but can increase air pollution.

I appreciate the concern Pete but I know what the codes mean, do u know any more about this situation? Now my engine stumbles when accelerating around 3000 to 4000 rpms

And my setup is an 2003 Audi A4 1.8t

You have bad O2 sensors heater circuits, and from previous posts looks like you changed the O2 and the code remained. So now the place to look is at the wires, and connectors providing power to the O2 sesnsor heater. May want to consult a wiring diagram for your car. There is no magic formula.

Fixed the problem, mybad
 

I was checking fuses before this all happened and I
Must of put the ECM 15A fuse in a unused port, which bassically controls all the sensors that throws those specific codes. So check twice when u are messing with fuses.

You deff need new Pre Cat 02's
 

The O2 code gets thrown when the heating element doesn't heat up fast enough to produce accurate readings or has failed completely. Bank 1 is pre cat. Get the bosch universal o2's (like $30.00 a piece) remove the old ones, cut the old wire at the sensor and splice to the universal, apply anti seize, torque'm & your good.

The SAI system codes are unrelated most likely and a complete separate problem as this only is in use on cold start ups. Check to see if anything is unplugged around the Kombi valve, if all is well there your purge valve may be the culprit as this appears to be an electrical issue.

The other codes are probably all relating to your MAF sensor. Try giving it a good cleaning. When its not working properly it causes misfires and all types of codes similar to what you've posted. You may need a new one.
Also be sure all vacuum lines are intact and in place as this can also cause the rest of the codes your car is throwing.

Does it idle like crap right now? If so MAF is a good candidate. Try cleaning/replacing this first & doing to o2's. Clear the codes after that & see if anything comes back. If so then worry about the SAI stuff.