Idle Problem

[PJF 111S]

S2 111s is suffering from erratic idle, resulting in engine repeatedely cutting out at low revs. May be unrelated but i did replace the battery last week after starting problems. Not been using car much lately due to crap weather.

[ChristianM]

Yes, my S2 111S did exactly the same thing in the same senario. The way I got it to stop in the end was by connecting an OBD II and loading some diagonstic software wich didn't show any error codes but did seem to cure the problem, maybe it reset the ECU in some way.

The USB OBD II cable is cheap enough on ebay and there is free software out there.

[NWTony]

Check your battery connections, mine were loose and it ran like apig, idling high and low, all over the place.

[Justin S]

poor battery will create a huge load on the alternator and also cause the electronics to cut out due to insuuficient voltage as the alternator is working overtime to charge the battery. Irratic idling is invariably linked to the IACV (idle air control valve) this allows air on a steppermotor to modulate to allow smooth running. These get bunged up and need cleaning out. although one bolt is a bugger to get to of the 4 on it. This may also link to the battery senario as the motor is also electrical. There is a reset for the IACV on the techwiki on SELOC. This may cure it. I was routing around my engine one day and knocked a breather from the inlet manifold to rocker cover and this caused my erratic idle. With fixing this and cleaning the IACV, the idle was very static afterwards.Good luck with sorting this.

[PJF 111S]

Thanks for the advice , ill check battery and investigate the other possibilities at the weekend. cheers.

[max-lakeside]

If you have replaced the battery it will have lost it idle settings, if you driving it, it will relearn its idle settings. you may have to do a few miles.

[PJF 111S]

Could be on to something there , been out today and whilst idle was a little erratic it didnt cut out at all.

[tertius]

I've had this problem intermittently with mine for ages. Nothing has fixed it - new TPS, cleaned IACV, new IACV, new TPS wiring - so if you find the problem I'd love to hear about it.