hi guys, i have a 02 A4 1.8T quattro, and something rather weird happened to it today.

i dunno, this may or may not be relevant, but my ESP light (the one with letters "ESP") and the circle+triangle+exclamation point light had come up before during a 5hr trip i took before christmas. they went away the same day after i had stopped at a friends place for a couple of hours.

so i had it in the back of my mind that i'd take it to the dealer to have the codes pulled some day until today the two aforementioned lights came up again as i was slowly driving out of the school garage and gently stepping on the break at a stop sign. i ignored them and drove to the grocery store on my way back home.

as i got back to my car after getting some stuff at the grocery store and was ready to back out of my parking spot. i noticed that if i step on the break pedal, the engine would rev up to 1500rpm with shifter still in P. as soon as i let go the break, it would come back down to 800rpm. i tried stepping on the break a couple more times, same thing. i was a bit confused and worried abut decided to leave anyway. as soon as i shifted to R, the two malfunction lights came up, but no more drama than that. the engine idled fine (800rpm) when i was stopped in R or D with break applied and i made it back home.

after i got back i decided to give it one more shot. i turned the engine off (shifter in P) and started it back up again. same thing (engine rev) would happen if i hit the break in P. but i also noticed that if i very slowly apply the breaks, it wouldnt rev.

now i will definitely be taking it to the dealer asap but also wanted to get some opinion from you guys. i really know not much at all about cars and can't even tell if the problem is electrical or mechanical, or maybe the on-board computer is at fault?

anyway, any suggestion is much appreciated.

some additional info: 84k miles on the car, all stock parts (maybe except for the temperature sensor), last check-up at an audi dealer in fall.

thanks a lot!