1999 Pontiac Grand Am

Computer problem
1999 Pontiac Grand Am 6 cyl Front Wheel Drive Automatic 174000 miles

Well I got my car inspected last month at the beginning, figuring I'd not put it off. It failed miserably, like 6 OBDII codes.

I got rid of (permanently) all but one, P0442, which says theres a small leak in the evap system.

I changed the gasc ap, got all the monitors up and running, and still comes up.

How much would it cost to get this repaired at maximum, minimum, and average?

Being not a huge problem (enough for failure inspection in NYS), could I leave the EVAP monitor incomplete while others are not, and simply get it inspected that way for a passing vehicle?
April 1, 2010.

If the gas cap didn't fix it, then it's possible there is a leak in one of the plastic evap tubes, or the canister purge solenoid is stuck open, thats on the canister. These systems are tested with a smoke machine that pumps smoke into the evap system, and where the smoke comes out, there is a hole. The solenoid is fairly cheap. It's located on the underside of the car near gas tank. The purge valve is in this picture, and is where the smoke gets pumped in.

Follow the line to find the solenoid.

Apr 1, 2010.