1993 Honda accord evap problem. not passing smog

[SlayrPhoenix]

My cousin has a 93 accord and she is having trouble passing smog. The ASM Emission test results stated that the NO (PPM) max:490 and 511 ave: 165 and 128 MEAS: 882 and 874 and both lines failed. When her dad told me about her car my first thought was to check her O2 sensor or her EGR valve. then i started to look around and that was the basic consensuses of what i thought. my next idea was to just give the car a quick tune up and change the spark plugs and wires, change the air filter, and clean the throttle housing and possibly the O2 Sensor just for safe measures. also thought maybe it needed a new CAT but not sure. i also saw that there gas cap could be lose too but its dark out right now so ill check it all tomorrow. but i just wanted to know if i should keep a look out for anything else that i didnt find or am missing. help would be GREATLY appreciated. she just got her license last week and this is her first car so id really like to help her out.

[hondaxpurt]

High NOx is usually a bad egr valve or ignition timing is off.

[hondaxpurt]

Whats all the other readings look like?

[SlayrPhoenix]

Whats all the other readings look like?

from what the paper said everything else on the car passed.

[hondaxpurt]

Get a timing light, check ignition timing, the check egr operation.

[SlayrPhoenix]

the timing seemed ok. but we will check it too. i changed the spark plugs and cleaned the air filter and that was a major IMPROVEMENT from what the car was doing a few hours before. my uncel said we need to adjust the idle up cus its idling at 5k and i tried moving the distributor but it wasnt doing anything. can u tell me where the idle adjustment screw is so that we can adjust it from that?

[hondaxpurt]

the timing seemed ok. but we will check it too. i changed the spark plugs and cleaned the air filter and that was a major IMPROVEMENT from what the car was doing a few hours before. my uncel said we need to adjust the idle up cus its idling at 5k and i tried moving the distributor but it wasnt doing anything. can u tell me where the idle adjustment screw is so that we can adjust it from that?

The throttle body has an idle adjustment screw on the front but leave that one alone. I would adjust the screw below the throttle butterfly. Open the plate just a little

[SlayrPhoenix]

ok the idle problem is fixed now. car shud be fine and pass smog if not the o2 may need to be changed and/or the egr will need to be replaced/cleaned but i think it shud be good now. thank you very much for the advice. if i run into any more problems i will not hesitate to ask