Hey guys. I recently started throwing p0505 code. I searched but couldn't find any info to my problem so would appreciate any help I can get.

Started about 2 weeks ago, I noticed my ses light was on so hooked up my code reader and it pulled 2 problems. 1) p0505 Iac malfunction or something like that and 2) was same thing just pending.

I switched over to e85 about a month ago and few days after my idle started to rise every now and then. Didn't think much of it since I didn't have any check engine lights on. Now my idle stays constant at 1500rpm after warm up. I have been told to clean the iac valve because it could be clogged with carbon.

Does any one have suggestions or has any body experienced this problem and solved it? Hope I don't have to replace the iac, saw they go for 300 from the dealer. Any help would be appreciated! I'm going to go take it apart right now and see If I can clean it. TFL

 

I don't have a listing for P0505 in my '03 service manual. However, I am told that it means that your idle speed continues to vary greatly from the ECU target. So, it is as you suspected.

 

I adjusted the screw on the throttle body lowering the rpm, now it seems to stay around 900-1000rpm. I'll update if the code cones back on.

 

I've been told (but never experienced) that if your idle is too high it will code.

Don't know which code.

Don't know if its true.

Just been told this.