I have a 98 accord with 63,000 miles that after sitting for two weeks in frigid weather began to have a surging idle from 700 rpm up to 2000. After 15 miles it idled normally but then displayed a code 505. I cleared the code but am wondering whether it will happen again. Honda wants 221.00 for a new one & they said they sell a lot of these. How hard is it to replace. It looks pretty simple in my honda service manual. Thanks for any help!!

 

code 505? Do you mean P0505?
Maybe the IACV needs cleaned?