N16 Nissan stalls / idles rough after changing battery. Relearn ?

Hi all,

(backstory)
Car wouldn't start, got NRMA out to jump start, and he tested the battery while car was running, to check alternator (14.## volts), he said alternator was OK, so we drove it home. Next morning, went to supercheap to get a new battery, car started OK, but at supercheap they tested battery and came back 'bad'. Bought a new Century battery, installed it....

Basically car is idling/stalling, which I 'think' might have to do with replacing the battery. Starting the car, it would start, then die. Only way to get it to start is to apply a little accelerator. After a few seconds, remove acceleration and car would idle, poorly (probably around 500rpm +/-). If I accelerate (1-2k rpm), and release foot, rpm would drop right down <500rpm, almost stalling, then it would pop back up again.

I have heard that replacing a battery can turn the ECU dumb, causing it to have to relearn, but was wondering if there's a chance there might be something else wrong with it?

I thought maybe fuel was dirty, but Mum said she fueled up a few days ago, but didn't notice any issues.
I checked air filter in case blocked, didn't seem to bad, a little dirty, but nothing suss.
Checked oil in case was low, and maybe causing friction in cylinder.. probably very unlikely, or pointless, but figured why not, while I had the hood up. (oil was 50% full, but needs changing)
Could be dirty sensor, haven't checked.

Anything else, or very likely that it just needs to relearn? If so, what's the best way to go about it? just start car and leave it idling in the drive way? Mum needs it for work, is that going to be an issue driving it ?

I tried an OBDII reader too, jut one of those ebay jobs, with the Torque (lite) Android app, but I got an error in Torque,

https://imgur.com/D4o1wSn

still loaded into Torque, but pretty much nothing would connect (except acceleration, which maybe ran off protocol 3, which I think Torque said was OK). I tried OBDLink, but wouldn't work unless I had one of their readers. Also tried BlueDriver, but wouldn't detect my reader :/.

Note: i just found this entry on wikipedia regarding the QG18DE engine;

OBDII – On-board Diagnostic System (codes can be read/erased by a variety of readers, e.g. Actron blaZt). Nissan Pulsar N16 Models without EuroOBD in Australia do not have OBDII.

If the car doesn't have OBDii reader.. what does it have? It has the port under the dash that connects a reader, so it must take something ?

Vehicle is a 2003 Nissan Pulsar N16 Auto 1.8L QG18DE engine.

Thoughts ?

Thanks in advance.

Changed afm? If that's not the issue probably looking ecu issues which requires coding to suit your keys or replacing the whole kit

Quote:

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Originally Posted by slow-sss

Changed afm? If that's not the issue probably looking ecu issues which requires coding to suit your keys or replacing the whole kit

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Didn't change anything, just replaced battery. Looking around, I see many mentions of having to re-learn the Idle Air intake, something to do with ECU losing info when removing battery. I tried a few procedures I came across, but nothing seemed to work. This is the latest one I tried,

http://afiaustralia.com.au/images/st...idle_fault.pdf

Though step #6 says to disconnect "Throttle position sensor (brown in colour) connector", but there is no brown connector, just a single green one. I service manual I found shows a diagram with a brown (throttle position sensor), and a Grey (closed throttle position switch), but our Pulsar just has a single green connector. When I disconnected / reconnnected that one, the accelerator when limp, couldn't rev the car. Had to turn car off for several seconds, then on again, now back to square one.

Does anyone know what port is in the Nissan Pulsar N16 (QG18DE) if it isn't OBDII ? Is it just the Nissan Consult port ?

In case the manuals I have are different to my Pulsar, anyone know what the correct manual procedure is ?

I meant have you tried replacing the afm as they are really cheap on ebay, tps relearn is a fly by wire/series 2 thing, think one of the procedures is the same as similar year xtrail. Im going back 15+ years here so not sure 100%

Quote:

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Originally Posted by slow-sss

I meant have you tried replacing the afm as they are really cheap on ebay, tps relearn is a fly by wire/series 2 thing, think one of the procedures is the same as similar year xtrail. Im going back 15+ years here so not sure 100%

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I'll have to have a look into it. Is it possible to check to see if the AFM is in working order ? I ended up cleaning the throttle body, was quite filthy, however, I couldn't clean the IAV as it was riveted to the throttle body.

https://i.imgur.com/tr2mZj3.jpg
https://i.imgur.com/LVRHNmM.jpg
https://i.imgur.com/F9QZ1es.jpg
https://i.imgur.com/POObkUY.jpg

Started car, started good. RPM went to around 1k, then slowly came down to 800rpm. Good!. Let car sit few minutes, no problem. Turned car off, started again, but, now it go upto 1500rpm and sits there. Turned off / on, same thing, tried again, same thing, 1500rpm :/. I might have to try and drive around a little, hopefully it'll adjust itself again, or maybe disconnected battery to reset ECU, and go from there ?

Still haven't been able to find a service manual for this one other than going to supercheap :/. I found this video (U.S I think), talking about relearning. The throttle pictured in the video looks the same as the one in the car.

https://www.youtube.com/watch?v=W1bsUedze5M

Another thing, I found this hose, doesn't seem to be connected to anything, can't see where it might connect to either. Is it suppose to be disconnected? Maybe a breather hose of some sort ?

https://i.imgur.com/Z947Epv.jpg


Regards, :)

[update] So I gave the relearn another try, and I 'think' I did it correctly, the idle dropped but only to 800rpm, then stayed there, but slowly came back to 1k rpm, so still higher than spec

This 1st video is from the throttle closed position procedure. You can hear the TB moving.

https://youtu.be/KQbnL5m5DmM

This is a video of the idle relearn. Sorry for the slowness of it, but you can see after starting the car, the idle comes down, then up. Eventually I tap the accelerator, you can see the RPM hang around 1.5k rpm before coming down. Seems to react not as it should?

https://youtu.be/XuxrJHvvFHM


Assuming I did it correctly, I'm not sure if taking it to a dealer for them to use their scan tool would be much different ?

I thought of opening the electronic throttle body (have to carefully remove the rivets to open though) and possibly cleaning it out, though this is a bit risky at this stage.

If the MAF sensor is dirty, can it affect the IACV reader, causing it to open more and let more air in?

I'm not sure of anything else to try, except try look for a vac leak again, and remove TB > inspect > apply copper gasket sealer (some ppl recommended it), maybe even change gasket.

something I don't get is, why after cleaning the TB the first time, after reinstalling everything and starting the car, it idled correctly, until I turned off and started again. Perhaps from TB cleaner got into the IAC and did something? Maybe dirty solvent from spraying got in then dried up on the sensor ?