As the title says I am throwing a P0505 code. It started after I had replaced the EGR valve, EGR tube, and EGR temperature sensor. These parts were replaced for the P1402 code I was throwing earlier. The parts took care of that code and the next day I see the P0505 code when I am parked and idling. The car was idling around 1,000 RPM's which I know is too high.

I conducted the idle learn procedure a few times yesterday and no change in idle. I disconnected the battery afterwards and came back to it this morning. Still no change in the idle, sitting at 1,000 RPM's. Ok, so I figured it must be the IAC valve acting up. I changed it today and tried the idle learn again, still no change.

At this point I am thinking something is limiting the idle learn procedure, where one of the pre-requisites wasn't in line. I'm not sure what it could be because I was careful to make sure I followed it to the tee. I also cleared the SES light before do the procedure just to be sure. Of course, the SES light showed up again after the car would sit and idle in P or N for more than a few minutes.

Should I take it to the dealer at this point and have them check it out? I'd really hate to take it down there. If there is something I'm missing let me know...

 

Bumpity bump bump....

 

Idle re-learn procedure at the dealer took care of the issue. Bummer, the home re-learn procedure didn't work...oh well. At least I got a car wash out of it.

 

Wow...I guess I need to do this as well. I changed my IACV and still got the code too. Thanks for sharing buddy.

 

let me know what happened.. i have the same problem also, changed it(iac), still have it, went to the deale(for programing)r, no solution. They want me to buy a new ecu for like 1500$ plus taxe. No money for that. Its driving me nuts. I need to fix this problem damn it!!!

 

sorry to say this topic has been beat to death is a well known and documented problem. The Iacv stepper motor has shorted out, and shorted out the Iacv circuit on ecu. This is the problem, you MUST replace Iacv and ECU at the same time to resolve this issue. If you replace the Iacv only, you've ruined the Iacv as the shorted ecu circuit has shorted the iacv. If you replace an ecu and connect to a bad iacv, you will short out the ecu.

 

wasn't there somebody who repairs the maxima ECU for lot less than that?

 

You are right...but I don't know if he is having the IAC / ECU problem or just replaced his IAC like I did. I replaced my IAC because I had an idling issue throwing the P0505 code. After replacing the IAC and doing an idle relearn procedure it still didn't take and I kept throwing the code until I took it in to the dealer to have them do the idle relearn with the Consult.

I got peace of mind with a new IAC valve and a car wash at least...

 

Yes...do a search, as the previous poster stated this topic really has been beaten to death. I only created this thread because I could not find an answer in my searching as it was a different issue than the IAC / ECU issue.

 

I just replaced the IAC and when I took the ECU out the chip that controls the IAC looks perfect! Now im stumped