temperature sensor in afm

[absidian]

Well, every car's idle will drop when D or R is engaged due to the additional load. It is the ICV's job to compensate for this and bring it back to normal idle speed (when instructed by the EMU since the ICV is just an actuator).

When that doesn't happen, then the ICV is a common and likely culprit.

but now that you mention it compensates OK for the aircon so ICV may still be working... but not as well as it should probably because the compensation for aircon is much less than for the drive load. Give it a nice clean and see what happens

 

[K.M.]

Please advice if the pic attached is the ICV of M43 engine?

Geof,

That is not the ICV. ICV is a round shape plastic with hose attach to it, near the front panel.

 

[K.M.]

Geof,

Does your car has a whistling sound when you switch off the engine? One of the mech told me, if got whistle sound then the ICV has a problem or ICV air leaking that causing the vibration during D and R.

Not sure true or not....

 

[jarance]

K.M.

You are right, as on idle with gear on N or P.. my idle is rock solid on 850rpm.. on the aircon the rpm jump up to 950rpm then drop back to 850rpm.

The questions now is .. should the ICV bring the rpm back to 850rpm when the gear is engaged? It should ya? As I notice on other car M52 engine, it drop when gear is engaged to D or R but it resume to 850rpm again.

Please advice if the pic attached is the ICV of M43 engine?

Maybe this would help you what an ICV look like.

 

[jarance]

Well, every car's idle will drop when D or R is engaged due to the additional load. It is the ICV's job to compensate for this and bring it back to normal idle speed (when instructed by the EMU since the ICV is just an actuator).

When that doesn't happen, then the ICV is a common and likely culprit.

but now that you mention it compensates OK for the aircon so ICV may still be working... but not as well as it should probably because the compensation for aircon is much less than for the drive load. Give it a nice clean and see what happens

Extract from Bentley Service Manual for E36. The guide below will give your some hint on how to check the ICV. Basically the ICV is an ON/OFF valve. However, by switching the valve ON-OFF-ON-OFF continuosly at various time duration, the ICV can regulate the amount of air into the air intake to control the idling speed. For the more savy people, the term is call PWM (not PMS - you dont want to go there).
PWM is short for pulse width modulation.

Yes, look or hear the buzzing sound when you engage the Air-con or engage or de-engage the gear..

As mentioned, check the throttle sensor as well.

 

[K.M.]

Beside the ICV, can the problem caused by the AFM and hoses leakage?

 

[jarance]

Beside the ICV, can the problem caused by the AFM and hoses leakage?

Maybe.. If it due to a sticky AFM vane, the idling speed would be eractic regarless whether you are in D or P or N mode.

but hose leakage is ONE of the problem of idling speed and will also cause engine to stall if the leak is big enough.

 

[pussy]

actually.. our bmw ICV is very advanced... other japanese makes can't be cleaned neither serviced need to buy new.. take for instance, Wira 1.6XLI.. hopeless.. costs also RM500++

 

[anaksarawak]

actually.. our bmw ICV is very advanced... other japanese makes can't be cleaned neither serviced need to buy new.. take for instance, Wira 1.6XLI.. hopeless.. costs also RM500++

I do agree with you..

But my mec taught me to serviced my mum's 1.6XLI Wira ICV after I have the internal plastic gears changed. (Problems the gear broked)

 

[K.M.]

OK...at least now I got some ideas why my rpm drop and not return to 850rpm when gear engaged to D and R.

Need to check again the ICV and hoses. Or just change all to new....

 

[anaksarawak]

OK...at least now I got some ideas why my rpm drop and not return to 850rpm when gear engaged to D and R.

Need to check again the ICV and hoses. Or just change all to new....

Many Mech adviced not to change new as it is expensive. Secondhand unit after service can be as good.