So I got the stage 1+ package, Decorsa exhaust, and a test pipe about a week ago. I love it its a rocket. Today though I wanted to try out the 100 octane mode. So I filled her up and tried it out. When I was driving around my ABS and ESP light came on. I cycled the key off and then on and it would start just turned over. I switched it back to 91 octane mode and after about 15 sec it started and ran fine. I cycled the key one more time and both lights went out and it started right up. It goes through this everytime I switch to 100. I hooked it up to my friends V.A.G. COM and pulled the code P1850-35-00 (CAN Data Bus Missing from ECU. I am a VW tech but have here seen anything like this before. I just dont see how switching modes triggers this code. Maybe it is something to do with the Motronic and ESP working together I dont know. Its an 02 A4 by the way w/1.8t

 

I meant to say that it wouldnt start

 

interesting
is it a botched reflash

 

it was reflashed by eurocode