I have 5 miles on the repair and I must say its idling at 800 RPM, running and shifting just as it should. Gonna put some more miles on it in the next few days to make sure the PO505 code and any other codes dont come back. Thanks to everyone who helped me along the way and a special thanks to Krismax for holding my hand and walking me through all of the BS. Thanks dude

 

Hi Mastermike,
how is your Maxima after the repair? It happened to me 5 years ago and just again today. Last time I paid over $2000 to the dealer to do it.

So in a nutshell:
Replace the IACV
Send out the ECM to get repaired
Do not swap or disconnected the Throttle Body?

 

Running great! Follow the steps and your car will be running trouble free in no time. 1) Remove bad IAC (note) don't loosen or remove the TPS on the side of Throttle body. 2) Remove ECM / computer. (note) ECM is on the drive shaft tunnel, down by your feet, under the radio. 3) Send ECM to: Module Repair Pros in Van-eyes California $200. 4) Order new IAC from Rock Auto $125 note (HITACHI ONLY) 5) While ECM and IAC are on order and getting fixed, disconnect the electronic motor mounts. 6) Install new IAC (note) you are doing the coolant bypass here. No coolant lines will be hooked to IAC. there will be 2 open ports on the IAC when you are done. 7) Install your rebuilt ECM . $325.00 and some dirty hands beats $2,000.00 . HAPPY MOTORING!!!!

 

Thanks so much Mastermike! 5 years ago, we had this failure on our 2001 Maxima and $2000 later the Nissan dealership replaced the ECU and IAC/Throttle Body.

The car had been parked 4 days when I turned on the car yesterday and it had a 1500 rpm idle (in park) and Service Engine Soon light turned on that's what scared me and brought back the deja-vu
The car has probably been driven 36,000 miles or less since that costly repair so I didn't expect it to happen for a few more years.

Today, I hooked up my friend's diagnostic computer and put the car in "on" position but didn't turn on the car
Got P1320 error code which is the ignition coils, right?

Would bad ignition coil cause the high RPM at idle?
Do you think I have the IACV/ECU issue or we don't know yet?

 

Yes, most likely.
But, there are other potential causes. Check this out: https://www.engine-codes.com/p1320_nissan.html

 

Thanks maxiiiboy, I read your awesome Preventing ECU Failures PDF.
So I'm going to disconnect the electronic engine mounts and try starting the car.
Can P1320 (potentially bad coils) fry the ECU?
Just trying to avoid frying the ECU? How would I know if ECU is fried (without opening it)?

 

No, P1320 can't directly fry the ECU - the problem is in the primary (low voltage) circuit.
I did have it ~ 2 yrs ago, replaced the coils, and everything was fine. Did not bother to diagnose it to the last nit/bit, just replaced the coils and moved on.

If the ECU is indeed fried, you should have driveability problems. If not, who cares .... . (I am oversimplifying a bit, but you get the point).

 

Any cheap but good coils you recommend?
i bought an aftermarket set a year back on eBay that always had service engine light so I went back to my originals. Car has 170k miles

 

Yes, here https://www.rockauto.com/en/catalog/...tion+coil,7060 - buy the Hitachi one (about $35 each).

 

Is it ok to just replace 1 or 2 coils (only the bad ones). Or should I replace all 6 together? Thanks again Maxiiiboy

 

Yes, but you have to find out which one(s) is/are bad. I didn't bother - just replaced all of them.

 

Awesome. I located both front and rear engine mount connectors (brown) but not sure what is the best way to disconnect without damaging.
Can I remove with my fingers? Do I push tabs together? Do I need pliers?

 

I have had no luck with cars lately so I’m going to try and see how it goes

 

Won’t that cause the engine light to come on?