Question: Idle Air Volume Relearn Procedure

[kscurl01]

'03 Murano, ~85,000 miles

Hey everyone, I recently had the battery replaced so thought it would be a good time to try the Air/Fuel Relearn Procedure (yes, different from the Idle Air Volume Procedure).

The good news is that my gas mileage went back up to the normal range of ~20mpg city and about ~26mpg highway (I was getting about 15-16mpg city).

The bad news is that since I had the battery disconnected for so long, my idle is now too low and will die upon normal operating temp restart (TSB NTB05-090.... details available on nissanhelp.com). Per the FSM, I performed the 3 idle relearning procedures associated with the idling, and the CEL/MIL/SES light flashed/stayed solid just like it says it should; however, I can't get the idle to change. I guess part of the reason is that during the last part, the FSM says to start the MO and let it idle for about 20 seconds. The problem is that I have to apply the accelerator a little to get it to stay at idle and not die.

The TSB does NOT give the manual procedures for performing these 3 idle relearn procedures... only gives the instructions for the shop to use the CONSULT-II diag tester/scanner. It does, however, say that if you can't get it to idle, then apply accelerator to 2000 RPM's, and slowly back down to idle for the 20-second duration. Maybe I'll try that tomorrow before taking it to the dealership.

I HATE to pay the dealership $$ when I know exactly what needs to be done but just don't have the darn multi-thousand dollar, off-limit CONSULT-II tester to get it done with!!!

Has anyone else ran into this problem? If so, how did you 'tweak' the manual idle procedure directions to get it to relearn the idle speed correctly?

Thanks for any help!

(BTW, I'm still fairly new to this forum as this is only my 3rd post. I haven't received alot of feedback on my previous posts, so I'm not feeling the love here fellas ... maybe I'm posting to the wrong forum section?)

[zebelkhan]

You are love! Except some of us may not know what to tell you so you may want to wait until a member with the right answer responds.

[kscurl01]

Well, part of the TSB stated that if you can't get the car to idle (before it dies), to take apart the intake ducting between the TB and the MAF sensor, and wipe the TB inlet clean. No need to use cleaner...

I was skeptical because I just had a the fuel injector service done at the stealership, and I was told my 3 different guys that they take the throttle body off and clean it as well. Have a look here at my throttle body and tell me what you think!!


Even though the throttle body was dirty, I think that the REAL issue was the stripped out "screw clamp" located between the MAF sensor and the resonator. It had a missing washer, so no matter how many times you would tighten the screw, the clamp would not tighten. The picture you see below has a washer that I put on myself in order to get it to tighten up...


This not only allowed me to complete the idle air volume learning procedure, but now the deep, throaty sound during acceleration (at 2000 RPM's) seems to be much better. It all makes sense...

This is my wife's car, and she bought it new in '03. Nobody besides Youngblood Nissan in Springfield, MO has EVER worked on this car, so needless to say, it sure pays to keep a close eye on whatever they do. There are 2 things here that I am fairly confident that they screwed up on!

Now, I can turn my attention to the failing CVT

[kscurl01]

Hey guys, as part of 3-tier idle learning procedure, I have a question about Step #2 on the Throttle Valve Closed Position Learning.

OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch “ON”.
3. Turn ignition switch “OFF” wait at least 10 seconds. Make sure that throttle valve moves during above 10 seconds by confirming the operating sound.

All of the other steps in the two other procedures say to leave the ignition in the "ON" position for a specified amount of time.... this one just says to switch it "ON". I assume that you can simply switch it "ON" and the switch it right back "OFF" for step #3?

I just want to make sure that I'm getting this whole procedure down right as our MO is sometimes lurching forward when pressing the accelerator, after a slight hesitation.

Thanks.