P300 and P 1780. engine Misfire and Park Neutral Position Unit?

not totally up on '01's. but since this is 22 hrs old and no one else has helped you, i'll give it a shot.

purdy sure if you solve the vacuum leak issues, that will clear the miss-fire and cruise control problems. cruise uses vacuum. and a generic vacuum leak would create a miss-fire condition. lean. but the ecm, via the anti knock sensor is at this point, compensating fuel mixtures adequately enough to not notice a driving/performance issue.

any auto parts store can help you with the rubber pcv grommet, elbow, or hose if needed. the pcv valve is a hard part. typically never go bad. just gets plugged up. but after removal, if you shake it and it rattles, it's good. if it doesn't, soak it in fuel for a while.

i could not find testing info on the pnp. but if she starts, you could likely for go that till you get testing info from say toy. they have given me info in the past.

also, if i'm not mistaken, the pnp also dbls as the back up light switch (auto transaxle only). so if you don't have those, that prolly the part of the switch that's bad. or maybe it's seeing an incomplete/open circuit within the back up light wires or at a light socket. might check fuses.

abs, that's usually an issue with a speed sensor at one of the wheels. but i can't find sh*t on testing those within this gen platform. sorry.