Check engine light always on

You still have a problem with the EVAP system....P0442 CHEVROLET - Evaporative Emission Control System Leak Detected Small Leak...Possible causes; Missing or loose fuel cap, Incorrect fuel filler cap used, Fuel filler cap remains open or fails to close, Foreign matter caught in fuel filler cap, EVAP canister or fuel tank leaks, EVAP system hose leaking, Fuel tank leaking....The P0442 code means that the control module has detected a small leak in the Evaporative Emission (EVAP). Loose fuel tank filler cap is the most common cause that triggers the P0442 code......The Powertrain Control Module (PCM) tests the Evaporative Emission (EVAP) system for the following conditions: - Large and small leaks - Excess vacuum - Purge flow during non-commanded conditions - Fuel Level and Fuel Pressure sensor faults - EVAP Purge and Vent Valve faults The PCM monitors the Fuel Tank Pressure sensor in order to determine the level of vacuum/pressure in the EVAP system. The PCM commands both the EVAP Purge Solenoid and the EVAP Vent Valve ON when the conditions are met in order to apply an engine vacuum to the EVAP system. The PCM commands the EVAP Purge Solenoid OFF once the system has reached a predetermined level of vacuum. This test verifies if a vacuum can be achieved in the EVAP system. Failure to develop a vacuum may be caused by a large leak or a restriction.

I was informed that I need a fuel tank pressure sensor on my 02 Monte Carlo SS 3.8L,average price $35.yet one may charge as much as $100.to install,if you can do it,its an easy fix. Advance Auto read a gauge and said I need a EGR value and do a smoke check to see if the hose has a small pinhole that is an easy fix to replace if needed.Either way EGR valve costs about $35.as well