E46 starts but doesnt keep idle

[Bradbrown]

Hi

I'm hoping someone can assist me in find out what could be wrong with my E46. I have 328i 1999 model, currently especially on hot days after driving a short distance my car wont keep it's idle.
It will start up but then dies. If you try to accelerate and keep the idle it doesn't work. after about an hour then everything seem normal.
I think something needs to cool down before it starts up again.
I've replaced the crank sensor recently hoping that the problem would be sorted but unfortunately I still have the same problem.

i'll appreciate any advise regarding this.
Thanks
Bradley

 

[ChrisBrand]

Problem may be one of the following but before you get your codes read we can only guess:
CCV pipes are damaged,
MAF Sensor,
Camshaft Sensors (Inlet and Exhaust).

Have the codes read.

 

[charly333]

sounds like the camshaft sensor needs replacing.
best is to get the codes read.

 

[Philip Foglar]

Could also be the MAF as said above. I suppose you could try and see if the engine will run with the MAF unplugged the next time it does this. It will store a fault, but that's a minor given the fact that you have an issue like this anyway.

 

[Spiro]

Idle control Valve ?



if you start car put foot on pedal to regulate even 1000rpm, then your problem might be here...

 

[Philip Foglar]

Idle control Valve ?



if you start car put foot on pedal to regulate even 1000rpm, then your problem might be here...

Plausible indeed!

 

[taristic92]

If there's an issue with the idle, it may be worth it to clean the intake system, including the maf, icc, and throttle body. It gives you a chance to also check the integrity of your intake boots and disa.

Sent from my SAMSUNG-SM-G925A using Tapatalk

 

[Bradbrown]

Thanks guys for your response.
So the same thing happened yesterday and I unplugged the MAF sensor plug like Philip Foglar advised and the car started up.
So I assume the sensor needs to be cleaned or replaced. So my next question is what will happen if I occasionally unplug the MAF sensor?

Thanks
Bradley

 

[Kimeran]

Moved to correct section

 

[Philip Foglar]

Thanks guys for your response.
So the same thing happened yesterday and I unplugged the MAF sensor plug like Philip Foglar advised and the car started up.
So I assume the sensor needs to be cleaned or replaced. So my next question is what will happen if I occasionally unplug the MAF sensor?

Thanks
Bradley

With the MAF disconnected, the engine is forced to run with a basic factory map and is not running with optimal parameters. So performance and economy won't be ideal, and I don't think it is advisable to drive the car like this in the long term. I would inspect the MAF sensor and invest in some good MAF cleaner, give it a clean and see if that helps. If the car has some sort of cold air induction oiled filter, like a K&N, there's a chance that it may have been over oiled at some point and sprayed some of the oil onto the MAF hot wires - this usually kills a MAF. Sometimes it can be rescued with a good clean, but since you cannot dare physically touch the hot wire, it's not always easy to clean. And these MAF sensors are not cheap!

 

[GPGrobler]

My E46 did not have any serious idling or running issues with an unplugged MAF sensor (I drove with it unplugged for almost two weeks before I realised it). There is something else that is wrong with our car.

 

[///GSPEC]

Definately MAF