Hi SR Gurus,
Yesterday I got an alarm/immobiliser installed into my NX. When I went to pick up my car, the installer told me that while he was running wires through the engine bay, he knocked on something and moved it (uh oh).

When I tried to start up the car, it began idleing veery strangely, as in, if I didnt give it some revs, it drops to zero, stalling the car. To try and compensate for this, the alarm installer tightened the throttle cable to raise the idleing rpm (uh oh #2).

The problem itself is quite dangerous, and very annoying. It seems to only do this when the engine is cold, as when it is warm and you start the car again, the revs fluctuate before settling on 700-1300 rpm.

I was wondering if anyone would have any clue as to what it may be. Would it be that the ECU would have been reset when the battery got disconnected? I thought that it may be this, but last time i disconnected the battery, it wasnt this bad.

Thanks for any help
Matt

P.S. My car stalled 7 times when leaving work today (bloody speed humps).

It may be your MAF ground. I bumped mine while replacing my cap and rotor and cleaning my throttle body. I don't know if they bumped yours too, but mine wouldn't idle for crap after.

If you want it check it look here.

http://www.se-r.net/engine/maf_ground.html

Hope you find out what it is. Make sure you post when you do.

Erik

I have the same problem as you man, but mine is because I installed a DET and the damn thing is still not running as good as I want it to. Anyways, you should try adjusting your base idle to see if that will help www.se-r.net/engine/adjust_idle.html
If that doesnt work, take it to a dealer and have them diagnose it. (thats what Im gonna do if I ever get money).
BTW, I've already tried regrounding the MAF, adjusting the TPS voltage, replacespark plugs and wires and the Idle Air Regulator assembly and had no luck with the damn problem :confused:

In the mean time just raise the idle a bit so you wont stall everytime you stop.

Good luck and keep us posted,
-Nick-

mine did the same...
i believe all you have to do is reset to the base idle. Have the shop pay for what they did. Go to nissan it was only one hour cost. so about 78$ hehe at least that was my price. and they also did the diagnose test. so either way its goooood way to go.. but try to get the shop pay for there mistake!!!!

err, Im a complete newbie, so what does the TPS look like?

The guy at the shop is pretty good about it, its just that he wants his 'mate' to fix it. Id rather fix it myself or have Nissan do it than that :).

Originally posted by tissue
err, Im a complete newbie, so what does the TPS look like?

The guy at the shop is pretty good about it, its just that he wants his 'mate' to fix it. Id rather fix it myself or have Nissan do it than that :).

On your TB (Throttle Body) towards the Firewall You should find a sensor connecting to the TB.

It's on the right side.. it's a plug like looking device. (This is on the opposite side of the Throttle Rotor, were your throttle connects to gas pedal/Cruse control servo. There should be only one plug on that side. This is your TPS. Take that sucker off by unplugging it and follow the directions for resetting the idle.

Hope this helps//

I think I know which one it is, I just dont want to pull out the wrong one :).

BTW Im in Aus, so my NX is a RHD car.

I have taken photos of the engine bay/around the TB's, could someone point out exactly which plug it is? cause I am stupid :)

The photos are at http://photos.yahoo.com/matthewspiers

The last two photos are of the other side (left) of the engine. Could someone also point out the EGR so I can bypass it?

Thanks so much

Matt

Thanks a million Horus. I have had an idle problem for a while. It seems like it does it only when it's cold but I have cleaned my egr, aac, replaced vacuum hoses etc. After reading your bit on the maf grounding, I went out and checked the resistance on my ground wire. I wiggled the harness and the reading jumped all over the place. So now I have a little project this weekend. Thanks again. :D

Ack! I adjusted my base idle but that did not fix it. Next I will try the MAF ground or just take it to Nissan :(

I had an idle problem for MONTHS on my NX...similar to yours, tissue. The culprit? The "Electronics (B)" fuse in the dash! Apparently the O2 sensor and a couple of other engine sensors run through that circuit to the ECU. Blown fuse = engine runs in limp mode.

Worth looking at...quick to check and cheap to fix!

Good Luck!