HELP codes 4, 20, and 41 along with oil leak.....

[MattEngels]

I've got codes 4, 20, and 41

I just got done swapping the motor over and got all 3 of thses codes on start up I had none before i swapped out the bad motor.

4 is crank angel sensor

20 is ELD bad voltage

41 Oxygen sensor heater

Going to start going through the diagnosing process and see where it gets me but figured i would share and see if anyone has some good insight on why i got all 3 of these after not having them at all.... car is in limp mode as well

And of course ive got an oil leak up near the oil presure sensor which made me think it might have cracked the block but i took it and the vtec solenoid out and I see no cracks. I checked to see if it was running out of the valve cover gasket and its dry.... is it possible to be leaking between the head and block near the vtec solenoid and oil presure switch? any insight would be great on both issues

[MattEngels]

Well I figured out what it was.... The headbolts were all loose.... the motor had its valve over not even bolted on and all the cam caps were loose I didnt think to see if someone had taken the head off..... So I got a new gasket in and the timing all set tomarrow im gunna go back and put her all back together. Ill never make this mistake again I usually take heads off used motors and check everything all out before hand but i was in a hurry and it got me his time....