When I start my girlfriends CRV the check engine and oil light come on. It goes away after the car warms up but it takes a while. What should I look for?

Also it has a cold start problem which i belive to be related to the IACV. I removed it, cleaned it and the problem was better but not 100%. IACV probably needs replacement.

 

Checked the codes and got the following.

Crank position sensor b
knock sensor 1
IACV fault (I knew that would be there)
catalyst efficiency below threshold

I cleared the codes and both the oil light and check engine went off. Why would the oil light go off with the check engine light? I drove it around for about an hour and turned it on and off a couple times and the lights are still off and everything runs smooth. I'm going to give the IACV a better cleaning, but i hope those other codes dont pop back up.

The sat with a dead battery in below zero temps for a week before the check engine light and oil light came on. Do you think sitting dead for a while can cause faults?