Harquebus

Ah, I see. I will tell them to do the proper procedure, reset the memory and perform the learning procedure (which is a well-published action when replacing ECUs and such) and/or do an ECU reflash update. If that fails, replacement is on the horizon.

And thanks for the word on CBM; they didn't leave me with a good feeling, i.e., 100% satisfaction. Caveat emptor.

Harquebus

I will certainly find that out and post it here for all interested parties...

Harquebus

The woman I am speaking to just told me that if the ECU has the current program already loaded into it, they can't load it again(?!?).
I dare say this car has never had a reason to have had anything done to the ECU to include having the most current program loaded into it. I think they just want to sell me a new/reman ECU which ain't cheap.

I am the second owner... Waiting for a response now (sighs).

vqmaxman

The only thing that will take care of the idle problems are the nissan consults. This has to be a relearn procedure. This is the only way you will fix the problems on the 02+ maximas.

maxiiiboy

NOT true, at least not for the 2000. I have never had to do any re-learning, and I have had my car for 15+ years. In the worst case, disconnect the battery overnight and you'll be fine.

aongch

Still stumped on why I'm only getting hot air into the car. All fuses look fine. Do I need to pull the console and examine the hot/cold air slider and doors? I didn't think working on the ECM caused this. Any ideas?

Btw, since the IACV install and hose bypass, idle is perfectly fine, no re-learn was needed.

Harquebus

Update: the ECU/ECM is still bad, could not be reflashed so I told the stealership to order a new one. It arrived and works but they do not want to gamble on pairing it permanently with a non-OEM IACV and the ones they can order cannot be guaranteed with a warranty (or some such) so I am ordering one myself and having it shipped there. Still saving money so far so that is good.

This is turning into a great fiasco IMO. What bothers me the most is the stealership is just a parts replacer and they don't readily perform diagnostics until you prod them; the same can probably be said for the vast majority of service depts but the fact that I'm telling them to reflash the ECU and to try other things just lowers my opinion of them even more (if that's possible).

Harquebus

Courtesyparts.com are out of stock on the IACV so it was ordered from oemnissanparts.com in TX. A bit cheaper too.

maxiiiboy

How much is the dealer asking for the "new" ECU?
At any rate, re. the matching problem: You can mitigate it by replacing fuse #58 (15A) in "Fusible Link and Fuse Box" with a 7.5 A fuse. I have been now running with a 7.5A fuse for more than 3 months. I also know that a 6A fuse blows within a week or two. This is not a guaranteed protection, but a much better protection than with the OEM set-up; more on this on this thread https://maxima.org/forums/5th-genera...d-seconds.html .

JUSTRIGIT

So how did everything turn out? Im goin thru a similar situation now

BronxSleeperMax187

Bypass IACV like others, if you got no heat all of sudden, you might have let air into the coolant system...burb it after checking for the leak and fixing it, you will smell it after driving (Antifreeze). If you got only heat like someone else, you should start by checking the amount of refrigerant in the system. If the amount is what the factory recommend, the check the "Refrigerant Pressure Switch" and the "Ambient Sensor". Sensor or harness could be damage.

Kitkat1023

Thanks for this thread! I have a 1996 Infiniti I30 with 116k. Same as the maxima, 01-03,I have been told. My car had a pending code when my mechanic noticed I had a coolant leak that was for a knock sensor. He reset the codes and added a lil coolant in overfill tank. The knock sensor pending code came back, no actual light on yet. I was going to order part but I started stalling when idling at a stoplight then almost got hit turning into a turn and it died. Had to towed to mechanic and he fixed knock sensor since that was still only pending code. Fixed it and pending code went away but as soon as he picked me up, it stalled when going slow on a turn again. He thought this was separate problem. Tried fuel cleaner and premium gas. Didn’t work. He wasn’t sure so I started researching. Saw that my IAC valve commonly gets clogged or fails in this car. No check engine light, no pending codes at this point...still intermittently stalling, more so when it’s warmer, even though a few times it’s happened when cold. I saw on a forum to try taking the IAC valve off and cleaning. Had a mobile mechanic come clean, carbon buildup was bad, he seemed to think it is the problem cause it was so dirty. We did sea foam in the fuel tank and down the intake manifold. He said if you can let it sit a day or two, it’ll clean it even better. He did turn the switch and reset codes. I started it two days later almost and smoked out the neighbors, holy smoke!!! No check engine lights came back on like he thought may happen. It seemed to idle correctly for a bit and I drove it about 20 miles, parked and It sat for an hour. When I went to start it again and drive, it started idling rough within a minute and tried to stall several times in that 20 mile drive back. It did stall fully two times and cranked back up when gassing hard. Then when driving going about 40mph, the tach started jumping a lil like it was struggling to go. I had to keep gassing it every stop after this to make it home. Seemed it got worse possible. Mechanic came back and made sure connected everything back. Drove it and it stalled shortly after warming it up a little. This time it stalled and when he tried to start again without gassing, it kept cutting off. After it sat for a few minutes, it cranked and stayed on for a minute without gassing and we drove back to house. Checked codes when back, still no light, and pending codes finally appeared for P0505 and 02 sensor. Cleared codes, restarted, now only showing pending 02. After reading this forum I see this can be a nightmare as it already has. I put $900 into this car the past three months and it’s getting close to reaching value not that it’s so old. 900 because it sat for a year, was grandmas car, and had to replace rear brakes and totors, radiator (was stemming and it cracked but got fixed right away, noise gone after replacing.) this other coolant leak was found shortly after this and it is towards back of engine, not in front, at least that’s where it smoked a little or I could smell burning. My questions are do I try and go further with this car or is it not worth it? It’s tough since it’s only 116k but I also know my axle is going. Now after reading, it could be many problems....is the coolant leaking where it could have fried ECM or do I just need to replace the IAC? Since cleaning the IAC, I didn’t think it needed idle learning but does it? I feel I could try to remove ECM and look at it but this would be a first, looks like a wrench is all I need. I’m outta money to keep guessing. Opinions please help?!

JUSTRIGIT

Kitkat1023