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Pedal Relearn, Throttle Body Relearn and Idle Relearn

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#1 ·
Pedal Relearn Procedure
Accerlerator Pedal Released Postion Learning is and operation to learn the full released postions of the accerlerator pedal by monitoring the accelerator pedal sensor output signal. It must be performed each time harness connector of accelearator pedal postion sensor or ECM is disconnected.

1. Make Sure the acceleartor Pedal is fully released
2. Turn Ignition switch ON and wait at least 2 Seconds.
3. Turn ignition switch OFF and wait at least 10 Seconds
4. Turn Ignition switch ON and wait at least 2 seconds.
5. Turn Ignition switch off and wait at least 10 seconds

Throttle Valve Relearn
Throttle Valve Closed Postion Learning is to learn the fully closed postion of the throttle valve by monitoring the throttle position sensor output signal. It must be performed each time harness of
electric throttle control actuator or ECM is disconnect.

1.Make sure accelerator pedal is fully released.
2. Turn ignition ON
3. Turn igntion switch OFF and wait at least 10 seconds. Make sure that the throttle valve moves during the 10 seconds by confrming the operating sound.
(You can hear the TB sound when you have key on and shifter in first gear and step on the gas. So you know what you listening for.)


Idle Air Volume Relearn Procedure
The Following Condtions Must be met in order for procedure to Work.

Battery Voltage :More than 12.9 volts at idle
Engine Coolant Temp 158-203 degrees Farenhiet
Electric Load Switch OFF i.e Air Condition, headlamps , rear defogger
Steering Wheel: Neutral Postion (Straight Ahead)
PNP Switch: OFF (Park Neutral Switch i.e. Clutch Switch...pretty sure)


1. Perform ACCERLEARATOR PEDAL RELEASED POSTIONS LEARNING
2. Perform THROTTLE VALVE CLOSED POSITION LEARNING
3. Start engine and warm it up to operation temperature
4. Turn igniton switch OFF and wait at least 10 seconds
5. Confirm Gas Pedal if fully realeased, then turn igniton switch ON and wait 3 seconds
6. Fully step on and release gas pedal 5 time within 5 seconds
8. Wait 7 seconds and fully step on gas and stay on until MIL stops blinking and is steady.
9. Fully release the Gas pedal within 3 seconds after the MIL has turned ON steady.
10. Start engine imediatly and let idle. Wait 20 seconds.
 
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#158 ·
Nah its either one way or the other. There is also a scanner that we call a Launch (I think by Snap On but actually not sure), that can relearn ECUs and other electronics.
 
#159 ·
Hey, i am having a little problem with my car too. A 2005 Sentra 1.8 Special Edition. I did all these procedure with my new mass air flow sensor on. My car is idling very roughly. I did the Pedal Relearn Procedure, Throttle Valve Relearn and Idle Air Volume Relearn procedures... While doing the Throttle Valvle Relearn thing, i heard my valve 1sec after putting my ignition to OFFf, but i didn't hear it for a full 10secondes as the procedure is saying... Anyway, i continued, the car was running good for like 15minutes after all these procedure. Before, car was going really bad. Though, now i restart my car and it is back to where i were... Still going bad...and now, there is a lot of Black smoke going of out my exhaust... My friend is saying it is because it is too rich, it is not oil....

Do you think i may need a new Throttle body ? I could try one for about 15-20$ on a junkyard... Do you know what model of TB are compatible with my 05 Senta 1.8 Special Edition ? ( i have 2.5 cold air intake and a 2.5 mass air flow sensor, with a Wrx 07 fuel pump ).

Now, i put back my old mass air flow sensor, idle is still rough, but not as rough with my newer MAF i bought from internet.... ONce reprogrammed, it was acting like my old sensor... but it went back to his initial state...
 
#160 ·
I am using two Mass Air Flow sensor. My old one, which is acting roughly on idle, but everything else is OK. My car is going 70% well with it.. My new one is acting horribly. car is stumbling anytime, the cas isnt understand when i press a the gas a little, very poor power, car is going 10% well....

I reprogrammed the new sensor with these procedures..
http://www.b15u.com/threads/99-Pedal-Relearn-Throttle-Body-Relearn-and-Idle-Relearn

After reprogramming all this, the new sensor was acting the same way as the old one...... I finnally stopped the car... When i start it again, idle is ok, but no power, and car is puffing black, and a lot ! I tried the procedure again but without success... I did put back my old MAF sensor.


During the procedures, while doing the Throttle Valve Relearn, i do not hear my throttle valve moving 10seconds after putting switch OFF,. I hear a little click click when i press gas on first gear, while it is stopped... But when i put ignition On and Off, no clicking sound for 10sec.... only a single click, that shuts after 1sec... May it be a sign of a faulty Throttle body ?

---
Throttle Valve Closed Postion Learning is to learn the fully closed postion of the throttle valve by monitoring the throttle position sensor output signal. It must be performed each time harness of
electric throttle control actuator or ECM is disconnect.

1.Make sure accelerator pedal is fully released.
2. Turn ignition ON
3. Turn igntion switch OFF and wait at least 10 seconds. Make sure that the throttle valve moves during the 10 seconds by confrming the operating sound.
(You can hear the TB sound when you have key on and shifter in first gear and step on the gas. So you know what you listening for.)



PLease, any idea on this ?
 
#161 ·
Our cars are very picky about with MAF you use. It has to be the stock maf.

Try to find someone and borrow their maf to see if yours have gone bad.
 
#162 ·
I have a question regarding idle relearn.
At the last step where it says to wait 20 seconds, am I supposed to turn the car off after 20 seconds or is that just the approximate time that it takes to level out the idle?

Also, I have to push my clutch in as well and I have a weak return spring on my clutch. I wonder if that is why some of us need to push our clutch in.
I've tried it dozens of times without clutch and the last 2 times I tried I was successful. One time in between the successful tries I forgot to push the clutch in and it wouldn't set the cel light blink.
 
#163 ·
So i hope you guys can help. Long story short my car wasn't accelerating all of a sudden one day so my buddy (who is a mechanic at a nissan dealership)suggested i replace my ECU. I replaced the ECU and that "partially" fixed my problem. Presently my car runs well after replacing the ECU but my mechanic buddy cannot get the idle relearn to work no matter how he tries (manually, nissan scanner etc). Specifically when he performs the idle relearn the idle goes to the level where it is supposed to be but the throttle loses response and you can't accelerate the car properly. With that said i can still drive the car (and i do sometimes) but the car idles high and evenutally goes back and forth from 1500 to 2500 rpm. Furthermore, we have replaced the throttle and mass air flow with brand new nissan dealer replacements :/ but no dice. I would have replaced a sensor like some have mentioned here but the sensor is not coming up on the scanner codes. The codes im getting are APP sensor, TP Sensor, MAF sensor, ECU and some other ones that i dont remember. PLEASE HELP !!! Thank you :)

P.S- Its a Nissan Sentra 2002 Spec-V SE-R
 
#164 ·
Sounds like you need to check out your wiring harness to me.
 
#166 · (Edited)
You'd want to confirm it's the harness before you decided to replace it.

So....visually inspect it real good. If you don't see anything then check and confirm juice is not making it threw the wires to the connector pins. Easy to check with the right gadget. The FSM will tell you what readings you should get from various pins on whatever connectors. Then if you are sure that's the problem, go bout deciding how you want to fix it.

I also wonder if a bad ground somewhere could cause all this. Idk though. Just wonder.
 
#167 ·
Going to bump this thread.
I was having p2138 accel pedal code recently so I replaced the pedal with the same pedal model. I reset the ecu and installed the pedal and went to start the car, and the car wouldnt start. It will crank and sounds like it wants to start but it will not fire properly. It seems as if the timing is all messed up. I have tried the pedal relarn and the ecu reset pedal dance and it did not help. I can't do the idle relearn because i cant even get the car to run.
The car will not start, it sounds like it is misfiring during cranking. What can I do to get it to run?
 
#171 ·
Next time....read the codes BEFORE you reset the ECU :facepalm:

ECzu, crank sensor, cam sensor, throttle body, could be all kinds of stuff.

When you do the throttle closed part of the relearn process...do you hear the little click of the throttle plate completely closing???
 
#170 ·
You have to diagnose the issue.
If the car started with the old pedal, I would put that one back in and see if it starts.
If it does, then you know that the issue is with the new one.
 
#172 ·
Im bringing this back from the dead because this helped me so much. In fact this its the reason I created an account just now so I could post this.
This process is not easy!!

I cleaned my TB because the car had sat for ever and I dunno when it was last cleaned. When I when to start the car it would surge from 1500-2000 rpm no matter what I did.

I eventually got the re learn process to work, and it did work. Im not exaggerating when I say I probably did this 15 times. And to make matters more confusing, when I did it, everything looked as though it was working. I got the blinking SES light, and then it went solid, and then I would start the car. No dice.

Anyways this is the process that eventually worked for me as I began just doing random slight differences in hopes something would work, I'm by no means saying this process is the correct one or know what I did different.

Do the on for 2 seconds off for 10 second process for 3 cycles. Some people said two, I did it for three.
Assuming all other conditions were met (Temp, voltage) I went forward with the relearn process. Previously when my SES light would go solid I would start the car immediately. This time I waited for 2 seconds, let go of the gas, waited another two full seconds, then started the car.
Finally it worked, revved to 2000 dropped to 1000, dropped nearly to 100 and almost stalled, came back up and settled around 650. The car runs great now with clean throttle body too.

I hope this helps someone because I searched and searched for reasons why it wasn't working and was on the cusp of driving it off a cliff since I can't afford the dealership.

Anyways, thanks for listening and stuff
 
#174 ·
Hey, I have no CEL, or SES light but when I push the clutch in while driving it hangs for like 2-3 seconds, by searching it was recommended to do the idle relearn, but I'm also seeing that you have to have a SES/CEL light. What do I have to do to fix this, it makes shifting extremely rough and slow. I've been double clutching to allow some time for the rpm to finally drop, but it's a bit hard when you have to shift quick.
 
#175 ·
Do all the relearns exactly and make SURE engine is up to temp, heater selector is not on defrost steering wheel straightforward. What do you mean you have no light? Has it been removed or tampered with? Follow the time in the relearn procedure with a timer. That should fix it. Double check that your connectors are all connected.. did you recent replace some.parts?

Look at the video on post #2 on this thread that may be easier to follow. Also,. Welcome to the forum If you fix the problem plz let everyone know. It helps others.
 
#177 ·
Some amount of rev hang is normal. Typically won't drop all the way down to normal idle immediately if you're moving. It should drop. But it won't immediately drop all the way down.

Could try cleaning your throttle body. Maybe it's dirty and sticking. May need a relearn after that.
 
#179 · (Edited)
I've been trolling here for way too long and as a thanks to this great community, I have decided to revive an old thread as one of my first posts lol.

As many of you have done, I had to take off my throttle body to clean it/install an intake etc... anyways, the main thingwas that the connector was unplugged and when plugged back in, I got the dreaded idle surge between 1500 and 2000 RPM. But there's more to it...

When I first tried to relearn the Idle Air Volume it didn't work so I thought, ok maybe I have to reset the ECM, so I unhooked the negative on the battery... big mistake! It was after that I realized from reading and searching a lot of the forums that many people experience the guage cluster crapping out and getting a code U1001 (communication error from ECM), P0500 (Vehicle Speed Sensor), and the P0462 (Fuel Level Sensor) after disconnecting the battery. Which is exactly what happen to me. BTW *** EVERYTHING was working fine before I took off the throttle body ***

The issue then becomes more serious with the U1001 code because without communication to the ECM, you can't relearn the TB with the pedal dance. I've read all over with people recommending replacing the VSS and the Fuel sensor to rid the codes... I believe this is all incorrect. The gauge is to blame (at least in this situation)... in fact the U1001 code is also due to the gauge not working which which I have no clue why aside from the fact that the MIL light is also not working when the guage is dead. Anyways, I had to fix the guage first due to the fact that without the MIL light it's impossible to do the pedal dance in addition to fixing the "communication error"

Apparently the solder on our gauges is prone to overheat and/or crack after time and they just crap out... why this happens when the batt is pulled I have no clue. I also have a Pathfinder with similar solder issues with the clock - a much easier fix as there are only 4 solder points. Anyways, I have no clue how to solder our gauges so I just took it out opened up the back and blew away some dust and gave all the solder joints a few taps with my finger (the solder joints on these circuit boards are very sensitive.. on the pathfinder clock I just had to press on the dash board to temporarily fix it). I then read about grounding issues behind the dash as well on a service bulletin. Turns out there is a 10MM nut on the left side just behind where the gauges mount to the dash where there's at least 6-10 wires grounding to the same nut. I loosened the nut and cleaned the bottom a bit and tightened it all back up. Plugged the cluster back in low and behold all the needles / odo and most importantly the MIL light was back working!!

I was so excited that I partially bolted the plastics back up and went out and drove the car to warm it up to try and do the pedal dance again after clearing the codes. After a short 5 to 10 min drive (as what everybody was advising to do - to warm up the engine AND the transmission) I tried the pedal dance like 10 times and was unsuccessful. 9 out of the 10 times my timing was correct and the MIL ends up doing the blinking and then steady and then I would start the car only to realize the idle still surges. This honestly makes you feel really frustrated and defeated.

Then I got thinking... the FSM says the engine has to be a certain operating temp for the relearn to work, and I've read that most people will wait 10 to 15 mins after their drive to do the relearn and then it works. Without an actual temp guage it's just guessing game as to when the engine is at the proper temperature and in fact I think after driving it, it is too hot to do the relearn. So this is what I did... let the car cool down completely. Do the first 2 steps: throttle close position and the pedal position and then TURN on the car to warm it up. The idle will be pretty steady (high around 1500). Turn the car off just after the idle starts to surge (i believe this is when the car "thinks" it is operating temp). Then do the third step - the Pedal dance. Do it EXACTLY like the FSM dictates... I've read alot of variations of the pedal dance, and I've done it twice but I've only been successful with the way the FSM shows. I also started the car immediately after the MIL light turned steady at the end... didn't wait x amount of seconds etc...

When you are successful, the sense of satisfaction is awesome.

Here are some things that I've read and tried, most of it in desperation and feeling of defeat but didn't work as well as a myth bust:

- Unplugging the throttle body connector momentarily/or for 2 or 3 seconds and then plugging back in while the idle is surging in hopes that it'll relearn by itself. After you unplug it, the idle stays steady but throttle becomes unresponsive until you restart the car... then the surging comes back.

- Doing the above with injectors 1 and 3 unplugged (this settles the idle but only due to it running on 2 cylinders)... the mentality here was to hope that the TB learns the calmer idle after plugging it back in... this did NOT work either.

- Driving around for 10 mins to "warm up the transmission" - this clearly was not done for the Relearn to work for me and I don't believe I read anything in the FSM for doing this... and in fact I think driving it around "overheats" the engine and puts it outside of the temperature spec for the relearn to work. For those of us who are doing the pedal dance, we clearly don't have Consult II nor any other program to see exactly what the temperature is, so I think this is the main variable that is contributing to the Idle Relearn to be unsuccessful. The other criteria is pretty trivial... 1) all electronics off 2) steering wheel straight 3) gear in park or neutral.

- I've read numerous times that while cleaning the TB you shouldn't move the plate and if you do you will pretty much need to replace it. Well when I cleaned my TB with brake cleaner I moved the plate multiple times as well as slamming it back shut etc... and it still works and I was still able to do the relearn. Hope this piece of info saves someone from thinking their TB is broken and going out to purchase one.

I hope I've put enough detail in here to have helped someone who is having difficulty doing the relearn. It gets really frustrating when you do it so many times and it still doesn't work, although it still drives with the surging idle, it gets annoying and embarassing when stopped at a stop light especially when you have an exhaust as well. Not to mention that it drives like poo cause you can't shift properly with a surging idle lol.

I had the luxury of knowing that EVERYTHING was working... so at one point even with 8 codes on the scanner I knew I didn't have to go out and buy a VSS or a Fuel sensor, or even throttle body... Which is what most people advise to do when those codes come up. I hope this will save someone from having to waste money on replacing a part and then realizing it wasn't the issue.

If at first you aren't successful, use a stop watch/timer and keep trying... it'll work!
 
#180 ·
So at nissan now, my idle is at 850 and drops really low at times it dies. If it dont die, itll fluctuate up and down from 850 to really low. I changed maf, changed plugs to autolites 5323's. Checked for vacuum leaks with carb cleaner, cleaned my throttle body after the bad idle. My plugs are @ .35. They were on stock plugs before with.45 same idle. I do haave a new TB in hand. Nissan could not do a relearn with the consult-2 since it needs to be idling tge guy said. They also said it felt like its misfiring, tgey cant check with the consult since the ecu has been reflashed by 2j. The consult really cant check in depth like that. Guess ill have to try this relearn procedure my self, with some beers and a watch. Any other suggestions? Car is heavily moddified. And tuned by joe, but he says its a problem on my end, which i can figure out, no codes either.... Thankyou
 
#187 ·
Is it still throwing any codes???
 
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