93 525i m50 engine
Ok I jump in the car after work and the brakes are really soft, so I stop at the atm around the corner and pop the hood to check the brake fluid. Fliud is low so I add dot 4 brake fluid and go pump the brakes about 4 or 5 times to see if they firm up. All of a sudden the car dies, I fire it right back up and the check engine light comes on. on the drive home the brakes do firm up and the check engine light goes out. The car sat all day today as I was off but about 7 o'clock i make a quick run to the store and notice the check engine light on again. When I get home I do the stomp test and get (1222 lambda control 1 )can someone please elaborate on this for me, I have no clue what this is. Did I cause this or was it just coincidental.

thanks,
darron