I've been having trouble getting the Idle Air Volume Learning to stick.

I upgraded to the 09 throttle body and am getting a slightly rough idle, surging when cruising at low RPM loss of power and the short term fuel trims are all over the place.

I've ruled out a vacuum leak.

I did the relearn with a Snap On Veris and it stuck for a few miles. All the symptoms went away and the fuel trims evened out. Unfortunately, it only lasted one trip and the symptoms returned. I've tried it again and again but it wont stick at all.

I tried letting it idle after the relearn, disconnecting the battery after the relearn and driving it immediately after but it wont take. Are there some other tricks to get it to stick or some other issue that may keep it from working properly?

The mods list below is mostly up to date. The car also has new plugs, new o2 sensors, new Hitachi MAF and an almost new battery. All quality parts.

 

I'm not sure I even did the relearn on my 5.7 swap.

It's a little tricky but car gauge pro does work. You just have to back out of it after the idle changes, then it sticks.

Did you try all of the pedal dance procedures?

 

I didn't think I'd have to either but I've been having this problem since I did the swap and couldn't diagnose it down to anything else. The first time I did it all the symptoms went away so I think it did need it.

I have car gauge pro but couldn't figure out how to do the relearn or much else. I haven't played with it much. I've been using Torque Pro to watch fuel trims etc....

I've never been able o get the pedal dance to work on my car. I've tried it numerous times with a stopwatch and can't get the CEL to flash. I'm pretty coordinated so I can't understand why I can't get it to work.

The Varis is a pretty high end piece of equipment on loan from a mechanic friend. We also tried it with another high end tool with the same results so I don't think it's an issue with the scanner.

 

^Just to add to some on the pedal dance...Yes its super tricky and only works best using a stop watch to time yourself..But there are few hidden quirks that prevent it from working (ie any of the windows being open a crack or down, and sunroof not being fully closed) For whatever reasons by design your call wont go into learn mode if any of those things trigger..

 

+1 Check ALL your accessories. Seeing as how finicky the process is, I'd even go so far as to make sure you're parked on level ground and have a full tank of gas.

 

Interesting. Does this apply when using a scan tool too? We had everything off but did have a window open. It just seems strange that it took once and now it doesn't seem to want to take. I think we had the door open and the window up the first time when it did take.

Yeah, level shop floor and also in my garage. Everything off and phone charger unplugged. A little under 1/2 tank of gas.

 

How do you do it with Car Gauge Pro? I can't seem to find anything in there other than ways to view information. I've been searching all over but it seems like a secret. People are talking about doing it but nobody says how.

 

Did you have the engine up to operating temp? I believe the threshold is 65C.

 

Yeah, had it up to temp and drove it right before.

 

once you've ensured the coolant temperature is up to where it should be. ..the way to get idle air volume relearn thru the car guage pro app is... .
before i go any further...this way im about to describe is the only way i have had it say idle air relearn successful. every other way it fails.

so given its an idle relearn one would assume car has to be running right?? well.....go and try this. it doesnt make sense in theory, but says successful. fluke???
1)get to operating temp
2)close windows, sunroof
2)tuen car off and leave key in acc position (all lights on)
3)perform idle relearn....watch it say idle learned successfully.

report back

 

Odds are it will fail. So, here's the steps needed in that case

1.)When it fails, turn off the car and exit CGP. Restart and get ready to do the relearn, again.

2.)Touch relearn and pay attention to the RPMs. As soon as the idle adjusts IMMEDIATELY press back over and over until you're out of the app (I kill the app, but I can do that with back button long press). Unplugging the obd2 adapter may work as well.
Wait a little bit to make sure it holds and cycle the engine to make sure it stuck.

3.) Try, again, if the rpm bounces back. I have successfully set the idle on maximas and altimas (maybe my sentra) with this method.

 

as i said...it doesnt seem to make "sense"...software coding fluke perhaps??
but it will say idle relearn successful. always does for me....

will try your method as well

 

How do I access the part of Car Gauge Pro that lets me do this? I've looked through it and can only see ways to view info but not where to affect anything other than clearing codes.

 

Self Test

 

Is it "on-board test" in diagnostics?

 

Under Diagnostics

 

Strange, my list is way different from that. I'm going to uninstall and reinstall the app. Maybe it hasn't been updating.

 

That did it. It must not have been updating. I've had the app for over a year and haven't used it much. I'll have to make sure I have automatic updates checked this time.

Thanks for helping me figure this out. I'll give it a try once I drive the car later today.

 

I've been playing with it and still can't get it to take. It just comes up saying "Not OK-Test was not successful"

Today I swapped back to the stock TB thinking the new one may be defective but it wont learn with the stock TB either.

Any other ideas?

 

Did you follow my instructions

Most of the time the test fails for me, too, but it will work every time with this method even if you have to try a few times. Timing is key b/c if the test goes too far, then the idle will go back up.

Someone else noticed this 1st as it's mentioned back on the original thread for car gauge pro.

 

It doesn't even start the test. When I select the relearn it goes right to the "Not OK" message after about one or two seconds.

 

Oh....

Sounds like the ECU is refusing like when one of the parameters isn't met. I think it hates you.

 

That's what I'm thinking. I've done everything by the book.

It seems like there's some other fault or error happening but I don't know what it could be. I'm considering taking it to Nissan and seeing if they'll give it to someone good with the Consult but that's a last resort.

 

Is your coolant temp showing correctly in the app?

BTW, just noticed your location. I love Santa Rosa Island.

 

I don't think I've checked the coolant temp in the app. Does it pull from the same sensor as the gauge?

Yeah, the beach is pretty nice. It's really been built up over the last few years though.

Where are you?

 

Idk which one it uses, but the only time I've ever had it not attempt to change timing/idle was when coolant temp was too low. It's worth a look.

I'm in St. Louis, but we used to vacation on Santa Rosa every year until back to back to back hurricanes (2000 I think) just ruined everything. Small businesses went under or quit, then the big hotels started and prices went sky high.

 

I'll look at the temp today when I take the car out. I know it's been up to temp when I've tried but a sketchy sensor could be throwing it off.

The beach has built up a lot since then. Lots of hotels, condos and new restaurants.
I don't really go out there much though. I'm much more into mountain biking than going to the beach.

Did you ever eat at Flounders on the beach? I worked for their parent company in Pensacola and they sent me out there to manage for one summer.

 

I sure have. I love seafood

 

when you look at the temp pid look at the idle rpm pid as well.

 

I'm having trouble even getting the idle air volume learn to even work. Let alone stick. What's up with that?

 

I have never tried it on a de-k. I always assumed it's for drive by wire only.

 

What do you mean drive by wire

 

The 2002+ does not have a cable that connects from the gas pedal directly to the throttle body like the 2001 and earlier years.
It's all electronic.

 

So will I be able to relearn with a 2001?

 

I just adjusted my idle stop screw and disconnected my battery overnight. Now its spot on.

 

Idle RPM is in the low 600 range.

Still can't get it to take. I swapped the stock TB back in and it still has the same symptoms and still wont relearn.

Took it to Ni$$an stealership and they tried it. They said it took but before they could drive it the service supervisor said to get the car out of there and they couldn't work on it again because it was modified. I've never heard of anything like that unless it was warranty work. Not a paying customer. I think that they just want to swap MAFs and change coils at $110 per hour. Any challenge and they're looking for an excuse to drop it. So much for my first and last ever trip to Nissan service.

Anyway, it didn't take so I'm right back where I was.

I'm thinking that there may be a bad memory chip in the computer now.

 

Which one is the stop screw?

 

standing on the drivers side looking at the throttle body its on the left side. manually move the butterfly and you will see the screw the butterfly lever rests on. mine had a red dot painted on it and i gather it was done to mark the location. let me know if you can't find it and i will take a pic and post it.

 

Ohhhh so you just adjust that to allow slack

 

yes... i unhooked the battery overnight then checked the idle the following morning using car gauge pro. my tach is a little off but car gauge pro verified that it was set at ~700 rpm.