Please could someone help. The other day I disconnected my battery and reconnected it on my mx5 nc 2.0 and since then the idle has been erratic, it idles between 500 and 1000 rpm going back and forth and then settles down. This happens each time I come to a stop. I had no issues prior to disconnecting the battery. Do I need to reset something or have I missed something. I only disconnected the battery as I was going to detail the engine but never did in the end.
Hi, the ECU just needs to reset ....leave the engine running for about 15 mins that should do it or go for a good long run . Easy peasy !Yep, get the engine fully up to temp on a run and it should be fine after that.
Mine did this after fitting a new steering wheel as the battery was disconnected, it took a journey of about 20mins before it settled back to normal.
It’s a common issue, the ecu needs to relearn.
When mine did this, it did so for about 15 miles of urban driving.
Tried what you guys suggested still no joy. Idle is still erattic and is winding me up now. Any more suggestions.
On my NB I can ground pin 10 in my diagnostic box to set base idle.
Not sure if you can do this on your NC though.
Have you solved it?