video of my weird idle

[scarecrow0529]

89 honda crx dx
here is a video
http://www.youtube.com/watch?v=KwFEO...ature=youtu.be
that is when i first fire it up but when it starts to warm up it will idle fine. it will only bog when i take off from a stop. it is throwing a code 20. i dont know what that is. lol. problems.

[scarecrow0529]

ground to fuse box question
89 crx dx d15b2
throwing code 20 so was told to check fuse box with key on and headlights on. it says it should only show 2v but was a little over 4v. just for the hell of it i used another ground wire to check and make sure ground was good so i touched one end to the fuse box ground and the other end i touched to the ground on the thermostat housing. it sparked and blew the battery fuse in the fuse box. the fuse was 50a the lid says it should be 60a. so my question is should i just replace the whole fuse box.