Ok so to make a long story short, I have a 98 ex. Had a CEL got misfire codes, put on a new distributor because my IAC is blocked off and that was my mechanics suggestion. With a new distributor it still idled low. Adjust the fast idle? screw, now the idle is fine but rough until its warm. Thing is I have an IAC, but its blocked off. And as I recall I didn't get the p0505 code before, but now I do. Could I just unplug the battery and reset the ecu so this can go away. I need to get my car inspected! Symptoms are the rough idle until I drive and earlier it was sputtering and shaking, but when I drove it home I was good. This CEL is annoying and so are the misfires!

 

The following is is assuming it's a manual EX with a two-wire IACV. The automatic has a three wire IACV and I'm not exactly sure how to check it.

When you say blocked off, you're talking about the air side right? The water lines really aren't necessary for operation though they help in extremely cold weather. A lot of people bypass the water side and it will still run properly.

Remove the IACV and try to blow air through the air passages. With no electricity applied, it should be closed. If it is stuck open try cleaning it with carb cleaner.

Then put it back on, unblocked, and see what happens.

 

its only connected by the wire. no vaccum or anything.