First a huge thanks to everyone one the forums. I almost have my car back to normal now.

So I had the P0505 error with the wonky idle 1100-1800 RPM, so after following the instructions on the forums multiple threads and have completed the following.

2001 Nissan Maxima, Automatic with 125000 miles

1. Replaced the IAC - Cleared code but the idle is still off
2. Cleaned intake and TB
3. Sent off ECM for repair (tested fine with zero issues - was tested twice on different sytems)
4. Replaced TPS and reinstalled ECM
5. Started up fine at 1100 RPM then idle shot up to 6000 and stays
6. Tested TPS good ohs at setting removed and reinstalled
7. Started to idle at 6000 RPM
8. Adjusted TPS manually but no effect but when removed or unplugged it has lower up/down throaty idle.
9. Turned off and on again with 6000 idle.


Any suggestions?

Thanks!!

Richard

If your idle is indeed as high as 6000RPM, I would strongly suspect the TPS and/or the associated wiring and/or connectors. The fact that when you unplug it, your RPMs drop, supports this hypothesis. Where did you get your TPS?

Sounds like the car needs an idle relearn, look up the idle re-learn preocedure for your max it's very simple procedure with turning the ignition specific ways and disconnecting the top TB connecter and reconnecting while idling and boom before you know it's good. If you fail keep trying, it can be difficult to get sometimes

i haven't replaced my TB before but I beleive it may need a relearn also but I think only an obd3 could do so. Try the idle relearn first tho

Aftermarket IAC? One of those $30 ebay ones?