2005 Audi A4 Turbo 1.8 Convert.
 

Just purchased vehicle and it failed smog due to check engine light being disabled. Codes: PO171 Bank 1/System too lean
PO507 Idle Control System RPM-Higher than expected
PO706 Transmission Range Sensor "A" Circuit Range Perf.
P3081
Today, the EPC light came on and vehicle began to stall when starting.


Can these problems be associated with bad coil packs or vacuum hose leaks?
I'm a first time Audi Owner and the guy that sold it to me had disabled the check engine light to hide all the problems. I'm a female and I do not know much about automotive mechanical issues. The dirt bag changed his number and I am stuck with this car that I cant smog. Can anyone suggest an Audi mechanic who can fix problems without charging a fortune? I live in Los Angeles.