M40 idle

[smithy318i]

Can any M40 owner tell me how their car idles at first start.

Mine pulses up and down between stall and 1K,
but with the ICV unpluged it stays at abuut 600 and doesn't surge.

cheers.

[Gwynleym10]

In my old SA 316i with the ICV that you sent me, when it was freezing it would idle around 1000rpm, then fall to normal after about 30-40 seconds.

My other one does a pretty similar thing, even though it had a head gasket leak....

[jonbuoy]

Mine does that, it's had a bad idle for the past month. First of all i changed the blue plug and everything was sweet but after a while it's deteriated and i think my afm is going up the wall. I un-plug the ICV and it run's at about 900 rpm

[dobbie82]

mine kinda fluctuates between 500 and 1500 m40's not well this winter?

will get round to sorting it when the tourer is up and runnin

[Rob_316i]

The M40 engine 316i that I just bought does this - it does exactly the same, goes from 1k to near stall and then back up again.

Took it out for a run and when warm it idles at 750 but when you stop at a junction it nearly stalls before settling at 750.

What will happen if you unplug the ICV - is it okay to run it like that ?

[Gwynleym10]

The M40 engine 316i that I just bought does this - it does exactly the same, goes from 1k to near stall and then back up again.

Took it out for a run and when warm it idles at 750 but when you stop at a junction it nearly stalls before settling at 750.

What will happen if you unplug the ICV - is it okay to run it like that ?
_________________

this is what my SA 316i did before i got another ICV for it.

[Rob_316i]

I checked the ICV though and it did what the Haynes manual said it should.

[Gwynleym10]

I checked the ICV though and it did what the Haynes manual said it should.

So did mine... but car dramatically improved when i put another one in!

[Rob_316i]

Hmm - okay, im beginning to regret the Haynes purchase.

Fought with the dash for an hour before realising the Haynes instructions on dash removal were for the 5 series.

Might try a new ICV

[smithy318i]

Dash removal article... http://www.strictlyeta.net/technical/dashboard.html

I have a spare ICV somewhere. So ill try that one.

[Rob_316i]

Thanks for that Smithy.

I managed to do it in the end but i swore a lot!

[JJ26]

My 316i M40 has done this every day for the last 7 months of owning the car. Ive changed the rotor arm, dizzy cap, fuel filter, intake hose (split), Blue injection temp sensor, thermostat, ht leads and cleaned/gapped the plugs. Not specifically for this problem il say. Its made no difference to this problem at all .

I tried another icv from a breakers and it was exactly the same. ive inspected the AFM for freeplay or stiffness but seems perfect. Kinda leads me to the only thing left to try.... ECU!

Note, i turned the emissions down 2 turns of the screw and this seems to have reduced the problem somewhat. Il stick the CO meter on it sometime see if its safe to turn down more, maybe il get more than 26 mpg out of this rattle box yet ;)