Revs problem

[whaleys]

Hi all,

A week or so the battery on my k-series Elise ran flat so I gave it enough of a charge to start the car (because I was wanting to go out in it) and then took it for a 5 min run and stopped off at my mum and dads. I decided to leave it running for 20 mins or so then stopped it. When I went to leave it started just fine but with any blip of the throttle when stationary the cars revs would increase and when dropping it would not stop at 800 rpm it would just stall. So I took it for a 20 min or so run and everything feels totally normal, when I pull up to lights the revs drop and hold at 800 as normal. If I have to pull forward a little, when I lift off the throttle the revs drop and it stalls. When that happens unless I start and move off straight away it will stall unless I catch it and very very gentley return the car myself to around 800 revs.

Before all this happened I had it serviced and it was totally fine and I drove it for a good 100 or so miles, it's just after the battery had died.

Any advice greatly appreciated as usual...

Thanks,
Graeme

[sls]

Had a quick word with my Guru (Ali) who has said it could be eithrer a IACV issue or the throttle pot?

[whaleys]

Hi all,

Thanks for the info sls, I hooked up a code reader and there are no error codes being reported. I started the car up and from cold it was fine, once it had warmed up it was struggling and a blip of the throttle and it stalled. Started it again blipped throttle and it went to stall so gently returned it to normal revs, I then disconnected the IACV and blipped throttle and it was totally fine.

I had read some other posts and Robin said that once its warmed up its prob not using the IACV but using the ECU to control idle, so not sure what it all means. It certainly looks like the IACV but is that just a red herring?

Thanks,
Graeme

[dirkpitt]

give the IAVC a good clean that may solve the problem, ive heard that they do get dirty from time to time and cause an issue....if its not that at least you can now rule it out, and move on.....

[robin]

I suspect it will need to relearn the correct IACV position, and cleaning out the IACV with some carb cleaner would not be a bad idea in case it's a bit sticky inside.

I think you can force it to relearn by key on, pump accelerator pedals 5-10 times, then key off again, leave for 30s, start engine but do not touch the throttle whilst cranking/first idle.

Chers,
Robin

[roadboy]

Yeah this is clearly all because of the flat battery. The idle generaly goes squiffy when the battery goes flat on S2s (Rover).

It will take a little bit of time but it will relearn the idle and be fine.

HTH

Dan

[whaleys]

Thanks for the advice guys, last night I took off the IACV, cleaned it and then reset it(apparently for the S2 K-series you turn the ignition to position 2 a number of times). Will leave it now to see what happens.

Cheers,
Graeme

[whaleys]

It's totally cleared up now, thanks for all the advice!

Graeme

[dirkpitt]

good to hear