does lid airbox stay closed with cold temperature?

[Highmast]

this morning i used my car with a heavy negative temperature (about -10°c)...
after oil and water engine at good level, i pushed the throttle more to ear the great carbone sound after 1 week park in my garage (12°C inside)...
But i realised that my carbon airbox refused to open the lid but nevertheless sport mode was on...

so, does electronic is sensible to cold temperature or it's a protection against frozen air and not open for not inhale directly?
Is somebody has meet this problèm before?

thanks for your experience

[_Nathan_]

Opens just fine, get someone to take a look while you rev it past 4k in sport mode. Might be stuck, common problem.

[RichW]

Mine was opening when stood still, but was intermittent whilst moving :(


Took the dam thing out! Cured! :D

[glendog74]

Remove flap - 5 minute job - problem gone! :-D

[Windowlicker]

I spoke to Thorney about their views on the whole flap removal thing, their opinion was , they wouldnt recommend it.
Basically, when running in normal mode, for the majority of the rev range the engine breathes through a much smaller inlet, and most work at part /light throttle/ low revs, with the flap removed, it would be running a bit rich as it compensates for the extra air it registers entering the engine.
Not a major problem as such, but having looked at the difference in the inlets behind the flap, (as in the bit used when the flap is closed, below 3,500 in sport and 6,000 in normal) there is a massive difference in potential airflow.
They said for the sake of £40 ish on a car of this value, why not just buy another flap actuator/solonoid, they run their cars with the flap in situ.

[SpineOnABap]

That's not right. Removing the flap doesn't mean the engine suddenly gets more air than it's expecting. The throttle opening controls how much air enters the engine. It's different if it's jammed shut so overall air flow is restricted, but being jammed open (or removed) makes sod all difference - with or without sport mode.
:beer:

[houlbt]

There was a similar thread on PureGT - See Here if you have Access (http://www.puregt.com/Forum/upload/showthread.php?t=22976)

But SpineOnABap is correct it makes no difference. Don't know what Thorney is on about? :clown:

[Mark CSL]

The only thing i would say is if it works without it why did BMW Motrsport fit it :whistle:

[shimmy]

There was a similar thread on PureGT - See Here if you have Access (http://www.puregt.com/Forum/upload/showthread.php?t=22976)

But SpineOnABap is correct it makes no difference. Don't know what Thorney is on about? :clown:

tom

that post still makes me laugh re BMS/Thorney

[houlbt]

The only thing i would say is if it works without it why did BMW Motrsport fit it :whistle:

Why do so many sports cars have exhaust valves these days?

[dave1]

noise regs

[SpineOnABap]

exactly

[Mark CSL]

The only thing i would say is if it works without it why did BMW Motrsport fit it :whistle:

Why do so many sports cars have exhaust valves these days?


I still think there is more to it than that.
But i do no mine stopped working and i put a new pontomoter on it
and all is good now.

[BMsport.com]

Finally, some one understands :wink: the flap is there for noise reasons. It has no bearing on the fuelling. The amount of air entering the engine is controlled by the throttle valves, not the flap and monitored by a MAP sensor. There are many CSLs out there with and without the flap. If it caused rich or weak running then the emission light would illuminate on the dash board. To say it must have a reason as it was fitted by BMW Motorsport is correct, noise. For the same reason the exhaust is quiet.

[M3_CSL]

probably someone should make an exhaust with a valve for the CSL too... while the exhaust valve is closed, the exhaust flow is like the original CSL exhaust... and when the sport button is depressed, both intake and exhaust valves will be opened for full race noise..

I used to use an electronic exhaust flap on my highly tuned N/A 350Z (revved to 8200rpm with full engine rebuilt and MoTeC), that car was quite loud with its exhaust, so a flap was needed to go around the suburban streets and i couldn't believe how much difference it made.... but with the flap closed, power loss was substantial and also the engine didn't like it at all

just a wild thought... :)

cheers,

richie

[englebert]

Someone should buy a Kreis-Seig... best sounding out there, goes from a normal exhaust to completely straight through at a touch of a button!

As said before, BMSport removed my flap. Went from their lowest peforming CSLs to one of the best!

[NZ_M3]

The amount of air entering the engine is controlled by the throttle valves, not the flap and monitored by a MAP sensor.

Kindly explain how does an individual throttle intake system operate on a MAP sensor without an intake manifold (to measure manifold absolute pressure??) - better still point to me an actual MAP sensor BMW part number on the CSL (I've yet to find one on realoem.com - and no not the one on the idle regulator lines - that controls idle). As far as I am aware the car runs without a MAF or MAP sensor - basically Alpha N tune on throttle position and air temp sensors.

Actually, if you can throw up a dyno graph showing that there's no torque loss without the flap operating in comparison to one with the flap operating.

[BMsport.com]

Map sensor part no. 13 62 7 833 561. It fits to the air rail so feeds from each throttle body, part no. 13 41 7 833 597.

[NZ_M3]

Map sensor part no. 13 62 7 833 561. It fits to the air rail so feeds from each throttle body, part no. 13 41 7 833 597.

That one's for idle control ... unless I am mistaken ...

[BMsport.com]

And even if it was alpha n, the air flow would still be controlled by the throttle valves, not the flap.

[NZ_M3]

And even if it was alpha n, the air flow would still be controlled by the throttle valves, not the flap.

This I agree with (unless the DME was clever enough to also read the flap actuator and run different mappings for an on/off position (unlikely I know) ... I just thought your MAP sensor comment was at odds to what I understood about the CSL fuel injection system.

[BMsport.com]

idle control part no. 13 41 1 733 090

[NZ_M3]

idle control part no. 13 41 1 733 090

Yeah I saw that ... cheers.

So the CSL is not a true Alpha N set up?? Or does the MAP sensor on the air line only come into play for idle control?? (what I had originally thought it did - otherwise it'd idle like crap ...

[BMsport.com]

The map sensor and airtemp sensor are there in place of the MAF meter. I tried looking for a BMW tech module on it, but they only have an explanation on the MAF not the MAP.

[NZ_M3]

The map sensor and airtemp sensor are there in place of the MAF meter. I tried looking for a BMW tech module on it, but they only have an explanation on the MAF not the MAP.

hmmm ... I've been told numerous times that the CSL is Alpha N mapping - the MAP sensor on the air line is only in relation to the idle control - maybe I'll unplug mine and see if it still drives :-D

I am familiar with the MAP sensors on Hondas ... not so on BMWs seeing they are usually all MAF screens. However on Hondas, turning them into ITBs require a separate vacuum canistor (of a correct volume) to calculate for MAP reading (which the CSL does not have- if you still wanted to run the MAP sensor) - but a Honda on ITBs can be turned into full Alpha N mode (say via a Hondata S300) in which case you can do without the vacuum canistor and just run the MAP for idle purposes.

Maybe I am getting myself confused ...

[BMsport.com]

If you unplug the map sensor, the car will still run, like if it had a maf, it would still run unplugged. With the technical advances of the ECU they will run with so many things unplugged like the crank sensor etc.

[Highmast]

I did few weeks ago a mesure of the engine power on a power dynamic bench.
and the result was: 347 cv at wheels for 8000 tr/min with lid open but only 306 cv with it closed!
Lid didnt't open because of a defaillant sensor of the temperature gearbox. http://www.cslregister.com/forum/viewtopic.php?t=918&highlight=
Maybe engine was also in security mode!

After repair the lid opened correctly to has today.
Doubtless the defect stayed in memory and affects has new the functioning.
I have to check connectors and return to bmw to make a control to erase défaults.

[NZ_M3]

If you unplug the map sensor, the car will still run, like if it had a maf, it would still run unplugged. With the technical advances of the ECU they will run with so many things unplugged like the crank sensor etc.

On a Honda it wouldn't ... hmmmm ... I am still not fully convinced that the car's fuel injection system is a MAP system rather than Alpha N - goes against the original marketing and subsequent informations I've seen and read for the car.

Any way, getting way off topic on this one.

Like I said before ... to be sure whether the flap actually does anything - a comparative dyno graph on one car with the flap operating and with the flap removed will put this myth to the grave.