NL Low Idle...

[neilrsayers]

Hi All,

My NL Is having issues with low idle when cold. It was getting down to about 500rpm and stalling when selecting a gear (auto), accelerating a little bit and backing off - such as when you reverse out of a car park.

I've replaced the Idle Air Control valve and cleaned the TB ... It was great for several days but today its playing up again!! I will admit that I didn't do the ecu reset, but it was working without any issues until today. I'll reset the ECU this afternoon and probably clean the MAF sensor.

Regardless, has anyone experienced any low idle issues similar to this?

[Alex86]

Gearbox oil change?

[neilrsayers]

The gearbox oil is only a few months old. It doesnt seem to be laboring - just not idling correctly when its cold as the RPM drops and stalls the vehicle

[Alex86]

Drain a little fluid, see if it’s still clean.

Nasty fluid in an auto can cause issues (might need the filter changed too).

Might need a proper flush.

But that’s about my level of knowledge with autos sorry.

[neilrsayers]

ecu reset seems to have done nothing... ive checked the old ISC and it had >400 ohms resistance between pins 2-1/3 and 5-4/6. I'll check the new one this afternoon if time allows, but it seems that its not working at all as there is no increased RPM when turning the A/C on. I assumed it was working when i did the ecu reset/idle relearn as it clicked as per many forum posts stated.

Does anyone have any voltages that i can check on the loom side of things to check for ECU/wiring faults? I've got a tactirx cable so i'll hopefully be able to get some sensor values to rule out any issues with TPS/coolant temp etc.

[stumagoo]

evoscan will give real time readouts of what the ecu is telling the ISC to do - it works with the tactrix cable. it also will tell you if the AC idles speed up is on and other info

[neilrsayers]

Ahhh. Checked the tps very quickly when I was at home this arvo. TPS is sitting at 12% when idling. I can't imagine this is good for the iacv. Will try a TPS recalibration this weekend

[[TUFFTR]]

12% is normal range for a Mitsu for idle. Ensure the car reaches 100% at WOT too with the car on ign.
Certainly do an ECU side check to ensure the plug is getting the voltage needed. Can't think of too much more at the moment

[neilrsayers]

The new ISC valve was cactus!!! The magnet broke in to 3 pieces!!!

What replacements do people use? Although I'm hesitant to buy anything due to the nl recall... But the idle issue drives me nuts